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WEBVTT

00:00.000 --> 00:03.080
 The following is a conversation with Rajat Manga.

00:03.080 --> 00:04.960
 He's an engineering director at Google,

00:04.960 --> 00:06.960
 leading the TensorFlow team.

00:06.960 --> 00:09.160
 TensorFlow is an open source library

00:09.160 --> 00:11.520
 at the center of much of the work going on in the world

00:11.520 --> 00:14.040
 in deep learning, both the cutting edge research

00:14.040 --> 00:17.720
 and the large scale application of learning based approaches.

00:17.720 --> 00:19.480
 But it's quickly becoming much more

00:19.480 --> 00:20.960
 than a software library.

00:20.960 --> 00:23.760
 It's now an ecosystem of tools for the deployment

00:23.760 --> 00:25.720
 of machine learning in the cloud, on the phone,

00:25.720 --> 00:29.840
 in the browser, on both generic and specialized hardware.

00:29.840 --> 00:31.920
 TPU, GPU, and so on.

00:31.920 --> 00:34.200
 Plus, there's a big emphasis on growing

00:34.200 --> 00:36.600
 a passionate community of developers.

00:36.600 --> 00:39.760
 Rajat, Jeff Dean, and a large team of engineers at Google

00:39.760 --> 00:42.720
 Brain are working to define the future of machine learning

00:42.720 --> 00:46.200
 with TensorFlow 2.0, which is now in alpha.

00:46.200 --> 00:49.120
 I think the decision to open source TensorFlow

00:49.120 --> 00:51.720
 is a definitive moment in the tech industry.

00:51.720 --> 00:54.360
 It showed that open innovation can be successful

00:54.360 --> 00:56.840
 and inspire many companies to open source their code,

00:56.840 --> 00:59.640
 to publish, and in general engage in the open exchange

00:59.640 --> 01:01.160
 of ideas.

01:01.160 --> 01:03.880
 This conversation is part of the artificial intelligence

01:03.880 --> 01:05.000
 podcast.

01:05.000 --> 01:07.760
 If you enjoy it, subscribe on YouTube, iTunes,

01:07.760 --> 01:09.600
 or simply connect with me on Twitter

01:09.600 --> 01:12.640
 at Lex Friedman, spelled FRID.

01:12.640 --> 01:17.880
 And now, here's my conversation with Rajat Manga.

01:17.880 --> 01:22.440
 You were involved with Google Brain since its start in 2011

01:22.440 --> 01:24.800
 with Jeff Dean.

01:24.800 --> 01:29.160
 It started with disbelief, the proprietary machine learning

01:29.160 --> 01:32.760
 library, and turned into TensorFlow 2014,

01:32.760 --> 01:35.760
 the open source library.

01:35.760 --> 01:39.040
 So what were the early days of Google Brain like?

01:39.040 --> 01:41.760
 What were the goals, the missions?

01:41.760 --> 01:45.080
 How do you even proceed forward once there's

01:45.080 --> 01:47.680
 so much possibilities before you?

01:47.680 --> 01:50.520
 It was interesting back then when I started,

01:50.520 --> 01:55.320
 or when you were even just talking about it.

01:55.320 --> 01:58.800
 The idea of deep learning was interesting

01:58.800 --> 02:00.400
 and intriguing in some ways.

02:00.400 --> 02:04.840
 It hadn't yet taken off, but it held some promise.

02:04.840 --> 02:08.680
 It had shown some very promising and early results.

02:08.680 --> 02:11.360
 I think the idea where Andrew and Jeff had started

02:11.360 --> 02:16.160
 was what if we can take this, what people are doing in research,

02:16.160 --> 02:21.560
 and scale it to what Google has in terms of the compute power,

02:21.560 --> 02:25.240
 and also put that kind of data together, what does it mean?

02:25.240 --> 02:28.240
 And so far, the results had been if you scale the computer,

02:28.240 --> 02:31.480
 scale the data, it does better, and would that work?

02:31.480 --> 02:33.360
 And so that was the first year or two.

02:33.360 --> 02:35.080
 Can we prove that outright?

02:35.080 --> 02:37.440
 And with disbelief, when we started the first year,

02:37.440 --> 02:40.760
 we got some early wins, which is always great.

02:40.760 --> 02:41.880
 What were the wins like?

02:41.880 --> 02:45.240
 What was the wins where there are some problems to this?

02:45.240 --> 02:46.560
 This is going to be good.

02:46.560 --> 02:49.640
 I think the two early wins were one was speech

02:49.640 --> 02:52.200
 that we collaborated very closely with the speech research

02:52.200 --> 02:54.760
 team, who was also getting interested in this.

02:54.760 --> 02:57.760
 And the other one was on images where

02:57.760 --> 03:03.120
 the cat paper, as we call it, that was covered by a lot of folks.

03:03.120 --> 03:07.440
 And the birth of Google Brain was around neural networks.

03:07.440 --> 03:09.280
 So it was deep learning from the very beginning.

03:09.280 --> 03:10.760
 That was the whole mission.

03:10.760 --> 03:18.960
 So in terms of scale, what was the dream

03:18.960 --> 03:21.040
 of what this could become?

03:21.040 --> 03:24.280
 Were there echoes of this open source TensorFlow community

03:24.280 --> 03:26.240
 that might be brought in?

03:26.240 --> 03:28.640
 Was there a sense of TPUs?

03:28.640 --> 03:31.120
 Was there a sense of machine learning

03:31.120 --> 03:33.680
 is now going to be at the core of the entire company?

03:33.680 --> 03:36.040
 Is going to grow into that direction?

03:36.040 --> 03:38.320
 Yeah, I think so that was interesting.

03:38.320 --> 03:41.320
 And if I think back to 2012 or 2011,

03:41.320 --> 03:45.240
 and first was can we scale it in the year or so,

03:45.240 --> 03:47.520
 we had started scaling it to hundreds and thousands

03:47.520 --> 03:48.080
 of machines.

03:48.080 --> 03:51.040
 In fact, we had some runs even going to 10,000 machines.

03:51.040 --> 03:53.840
 And all of those shows great promise.

03:53.840 --> 03:56.760
 In terms of machine learning at Google,

03:56.760 --> 03:58.760
 the good thing was Google's been doing machine learning

03:58.760 --> 04:00.200
 for a long time.

04:00.200 --> 04:02.120
 Deep learning was new.

04:02.120 --> 04:05.000
 But as we scale this up, we showed that, yes, that was

04:05.000 --> 04:07.840
 possible, and it was going to impact lots of things.

04:07.840 --> 04:11.160
 Like, we started seeing real products wanting to use this.

04:11.160 --> 04:12.720
 Again, speech was the first.

04:12.720 --> 04:15.120
 There were image things that photos came out of

04:15.120 --> 04:17.360
 in many other products as well.

04:17.360 --> 04:20.120
 So that was exciting.

04:20.120 --> 04:23.120
 As we went into with that a couple of years,

04:23.120 --> 04:25.760
 externally also academia started to,

04:25.760 --> 04:27.760
 there was lots of push on, OK, deep learning's

04:27.760 --> 04:30.520
 interesting, we should be doing more, and so on.

04:30.520 --> 04:35.560
 And so by 2014, we were looking at, OK, this is a big thing.

04:35.560 --> 04:36.680
 It's going to grow.

04:36.680 --> 04:39.400
 And not just internally, externally as well.

04:39.400 --> 04:42.240
 Yes, maybe Google's ahead of where everybody is,

04:42.240 --> 04:43.600
 but there's a lot to do.

04:43.600 --> 04:46.640
 So a lot of this start to make sense and come together.

04:46.640 --> 04:51.080
 So the decision to open source, I was just chatting with Chris

04:51.080 --> 04:53.360
 Flattner about this, the decision to go open source

04:53.360 --> 04:57.040
 with TensorFlow, I would say for me personally,

04:57.040 --> 05:00.000
 seems to be one of the big seminal moments in all

05:00.000 --> 05:01.680
 of software engineering ever.

05:01.680 --> 05:04.600
 I think that when a large company like Google

05:04.600 --> 05:08.680
 decides to take a large project that many lawyers might argue

05:08.680 --> 05:12.840
 has a lot of IP, just decide to go open source with it.

05:12.840 --> 05:15.200
 And in so doing, lead the entire world in saying,

05:15.200 --> 05:19.280
 you know what, open innovation is a pretty powerful thing.

05:19.280 --> 05:22.320
 And it's OK to do.

05:22.320 --> 05:26.400
 That was, I mean, that's an incredible moment in time.

05:26.400 --> 05:29.280
 So do you remember those discussions happening?

05:29.280 --> 05:31.320
 Are there open source should be happening?

05:31.320 --> 05:32.600
 What was that like?

05:32.600 --> 05:36.840
 I would say, I think, so the initial idea came from Jeff,

05:36.840 --> 05:39.320
 who was a big proponent of this.

05:39.320 --> 05:42.400
 I think it came off of two big things.

05:42.400 --> 05:46.280
 One was research wise, we were a research group.

05:46.280 --> 05:50.240
 We were putting all our research out there if you wanted to.

05:50.240 --> 05:51.680
 We were building on other's research,

05:51.680 --> 05:54.920
 and we wanted to push the state of the art forward.

05:54.920 --> 05:56.800
 And part of that was to share the research.

05:56.800 --> 05:58.920
 That's how I think deep learning and machine learning

05:58.920 --> 06:01.360
 has really grown so fast.

06:01.360 --> 06:04.280
 So the next step was, OK, now word software

06:04.280 --> 06:05.280
 help for that.

06:05.280 --> 06:09.720
 And it seemed like they were existing a few libraries

06:09.720 --> 06:12.160
 out there, Tiano being one, Torch being another,

06:12.160 --> 06:13.960
 and a few others.

06:13.960 --> 06:15.400
 But they were all done by academia,

06:15.400 --> 06:19.000
 and so the level was significantly different.

06:19.000 --> 06:22.040
 The other one was, from a software perspective,

06:22.040 --> 06:27.120
 Google had done lots of software that we used internally.

06:27.120 --> 06:29.120
 And we published papers.

06:29.120 --> 06:31.680
 Often there was an open source project

06:31.680 --> 06:33.600
 that came out of that, that somebody else

06:33.600 --> 06:35.440
 picked up that paper and implemented,

06:35.440 --> 06:38.280
 and they were very successful.

06:38.280 --> 06:40.920
 Back then, it was like, OK, there's

06:40.920 --> 06:44.200
 Hadoop, which has come off of tech that we've built.

06:44.200 --> 06:46.240
 We know that tech we've built is way better

06:46.240 --> 06:47.880
 for a number of different reasons.

06:47.880 --> 06:51.680
 We've invested a lot of effort in that.

06:51.680 --> 06:54.320
 And turns out, we have Google Cloud,

06:54.320 --> 06:57.520
 and we are now not really providing our tech,

06:57.520 --> 07:00.520
 but we are saying, OK, we have Bigtable, which

07:00.520 --> 07:02.080
 is the original thing.

07:02.080 --> 07:05.280
 We are going to now provide HBase APIs on top of that, which

07:05.280 --> 07:07.480
 isn't as good, but that's what everybody's used to.

07:07.480 --> 07:10.960
 So there's like, can we make something that is better

07:10.960 --> 07:12.320
 and really just provide?

07:12.320 --> 07:14.320
 Helps the community in lots of ways,

07:14.320 --> 07:18.320
 but it also helps push the right, a good standard forward.

07:18.320 --> 07:19.960
 So how does Cloud fit into that?

07:19.960 --> 07:22.680
 There's a TensorFlow open source library.

07:22.680 --> 07:25.800
 And how does the fact that you can

07:25.800 --> 07:28.240
 use so many of the resources that Google provides

07:28.240 --> 07:31.480
 and the Cloud fit into that strategy?

07:31.480 --> 07:34.920
 So TensorFlow itself is open, and you can use it anywhere.

07:34.920 --> 07:38.360
 And we want to make sure that continues to be the case.

07:38.360 --> 07:42.080
 On Google Cloud, we do make sure that there's

07:42.080 --> 07:43.800
 lots of integrations with everything else,

07:43.800 --> 07:47.280
 and we want to make sure that it works really, really well there.

07:47.280 --> 07:50.080
 You're leading the TensorFlow effort.

07:50.080 --> 07:52.360
 Can you tell me the history and the timeline of TensorFlow

07:52.360 --> 07:55.880
 project in terms of major design decisions,

07:55.880 --> 08:01.240
 like the open source decision, but really, what to include

08:01.240 --> 08:01.600
 and not?

08:01.600 --> 08:03.600
 There's this incredible ecosystem that I'd

08:03.600 --> 08:05.680
 like to talk about, there's all these parts.

08:05.680 --> 08:12.120
 But if you just some sample moments that

08:12.120 --> 08:15.960
 defined what TensorFlow eventually became through its,

08:15.960 --> 08:19.400
 I don't know if you were allowed to say history when it's just,

08:19.400 --> 08:21.240
 but in deep learning, everything moves so fast

08:21.240 --> 08:23.400
 in just a few years, it's already history.

08:23.400 --> 08:24.880
 Yes, yes.

08:24.880 --> 08:29.760
 So looking back, we were building TensorFlow.

08:29.760 --> 08:34.240
 I guess we open sourced it in 2015, November 2015.

08:34.240 --> 08:39.800
 We started on it in summer of 2014, I guess.

08:39.800 --> 08:42.960
 And somewhere like three to six late 2014,

08:42.960 --> 08:45.320
 by then we had decided that, OK, there's

08:45.320 --> 08:47.080
 a high likelihood we'll open source it.

08:47.080 --> 08:49.560
 So we started thinking about that and making sure

08:49.560 --> 08:51.320
 that we're heading down that path.

08:53.960 --> 08:56.280
 At that point, by that point, we'd

08:56.280 --> 08:59.280
 seen a few lots of different use cases at Google.

08:59.280 --> 09:01.200
 So there were things like, OK, yes,

09:01.200 --> 09:04.160
 you want to run in at large scale in the data center.

09:04.160 --> 09:07.480
 Yes, we need to support different kind of hardware.

09:07.480 --> 09:09.400
 We had GPUs at that point.

09:09.400 --> 09:11.880
 We had our first GPU at that point

09:11.880 --> 09:15.760
 or was about to come out roughly around that time.

09:15.760 --> 09:18.640
 So the design included those.

09:18.640 --> 09:21.760
 We had started to push on mobile.

09:21.760 --> 09:24.880
 So we were running models on mobile.

09:24.880 --> 09:28.080
 At that point, people were customizing code.

09:28.080 --> 09:30.280
 So we wanted to make sure TensorFlow could support that

09:30.280 --> 09:34.120
 as well so that that became part of that overall

09:34.120 --> 09:35.200
 design.

09:35.200 --> 09:38.040
 When you say mobile, you mean like pretty complicated

09:38.040 --> 09:39.960
 algorithms of running on the phone?

09:39.960 --> 09:40.480
 That's correct.

09:40.480 --> 09:42.680
 So when you have a model that you

09:42.680 --> 09:45.200
 deploy on the phone and run it there, right?

09:45.200 --> 09:47.800
 So already at that time, there was ideas of running machine

09:47.800 --> 09:48.720
 learning on the phone.

09:48.720 --> 09:49.240
 That's correct.

09:49.240 --> 09:51.360
 We already had a couple of products

09:51.360 --> 09:53.240
 that were doing that by then.

09:53.240 --> 09:55.480
 And in those cases, we had basically

09:55.480 --> 09:59.280
 customized handcrafted code or some internal libraries

09:59.280 --> 10:00.080
 that we're using.

10:00.080 --> 10:03.280
 So I was actually at Google during this time in a parallel,

10:03.280 --> 10:04.440
 I guess, universe.

10:04.440 --> 10:09.240
 But we were using Theano and CAFE.

10:09.240 --> 10:11.560
 Was there some degree to which you were bouncing,

10:11.560 --> 10:15.440
 like trying to see what CAFE was offering people,

10:15.440 --> 10:17.920
 trying to see what Theano was offering

10:17.920 --> 10:21.320
 that you want to make sure you're delivering on whatever that

10:21.320 --> 10:23.680
 is, perhaps the Python part of thing.

10:23.680 --> 10:27.440
 Maybe did that influence any design decisions?

10:27.440 --> 10:27.880
 Totally.

10:27.880 --> 10:30.840
 So when we built this belief, and some of that

10:30.840 --> 10:32.920
 was in parallel with some of these libraries

10:32.920 --> 10:36.600
 coming up, I mean, Theano itself is older.

10:36.600 --> 10:41.080
 But we were building this belief focused on our internal thing

10:41.080 --> 10:42.880
 because our systems were very different.

10:42.880 --> 10:44.480
 By the time we got to this, we looked

10:44.480 --> 10:47.040
 at a number of libraries that were out there.

10:47.040 --> 10:49.240
 Theano, there were folks in the group

10:49.240 --> 10:52.080
 who had experience with Torch, with Lua.

10:52.080 --> 10:54.720
 There were folks here who had seen CAFE.

10:54.720 --> 10:58.800
 I mean, actually, Yang Cheng was here as well.

10:58.800 --> 11:02.960
 There's what other libraries?

11:02.960 --> 11:04.880
 I think we looked at a number of things.

11:04.880 --> 11:06.800
 Might even have looked at Jane and her back then.

11:06.800 --> 11:09.320
 I'm trying to remember if it was there.

11:09.320 --> 11:12.240
 In fact, yeah, we did discuss ideas around, OK,

11:12.240 --> 11:15.280
 should we have a graph or not?

11:15.280 --> 11:19.280
 And they were supporting all these together

11:19.280 --> 11:21.880
 was definitely, you know, there were key decisions

11:21.880 --> 11:22.560
 that we wanted.

11:22.560 --> 11:28.680
 We had seen limitations in our prior disbelief things.

11:28.680 --> 11:31.320
 A few of them were just in terms of research

11:31.320 --> 11:32.280
 was moving so fast.

11:32.280 --> 11:34.520
 We wanted the flexibility.

11:34.520 --> 11:36.280
 We want the hardware was changing fast.

11:36.280 --> 11:39.160
 We expected to change that so that those probably were two

11:39.160 --> 11:41.400
 things.

11:41.400 --> 11:43.320
 And yeah, I think the flexibility in terms

11:43.320 --> 11:45.280
 of being able to express all kinds of crazy things

11:45.280 --> 11:46.840
 was definitely a big one then.

11:46.840 --> 11:48.920
 So what the graph decisions, though,

11:48.920 --> 11:53.720
 with moving towards TensorFlow 2.0, there's more,

11:53.720 --> 11:56.680
 by default, there'll be eager execution.

11:56.680 --> 11:59.160
 So sort of hiding the graph a little bit

11:59.160 --> 12:02.120
 because it's less intuitive in terms of the way

12:02.120 --> 12:03.520
 people develop and so on.

12:03.520 --> 12:06.720
 What was that discussion like with in terms of using graphs?

12:06.720 --> 12:09.320
 It seemed it's kind of the theano way.

12:09.320 --> 12:11.600
 Did it seem the obvious choice?

12:11.600 --> 12:15.720
 So I think where it came from was our disbelief,

12:15.720 --> 12:18.560
 had a graph like thing as well.

12:18.560 --> 12:19.720
 It wasn't a general graph.

12:19.720 --> 12:23.160
 It was more like a straight line thing.

12:23.160 --> 12:25.000
 More like what you might think of Cafe,

12:25.000 --> 12:28.840
 I guess, in that sense.

12:28.840 --> 12:31.080
 And we always cared about the production stuff.

12:31.080 --> 12:33.480
 Even with disbelief, we were deploying a whole bunch of stuff

12:33.480 --> 12:34.440
 in production.

12:34.440 --> 12:37.960
 So graph did come from that when we thought of, OK,

12:37.960 --> 12:40.800
 should we do that in Python and we experimented with some ideas

12:40.800 --> 12:44.680
 where it looked a lot simpler to use,

12:44.680 --> 12:47.880
 but not having a graph meant, OK, how do you deploy now?

12:47.880 --> 12:51.080
 So that was probably what tilted the balance for us.

12:51.080 --> 12:52.880
 And eventually, we ended up with the graph.

12:52.880 --> 12:55.320
 And I guess the question there is, did you?

12:55.320 --> 12:59.800
 I mean, production seems to be the really good thing to focus on.

12:59.800 --> 13:02.400
 But did you even anticipate the other side of it

13:02.400 --> 13:04.560
 where there could be, what is it?

13:04.560 --> 13:05.240
 What are the numbers?

13:05.240 --> 13:08.920
 Something crazy, 41 million downloads?

13:08.920 --> 13:09.400
 Yep.

13:12.680 --> 13:16.240
 I mean, was that even like a possibility in your mind

13:16.240 --> 13:19.120
 that it would be as popular as it became?

13:19.120 --> 13:24.880
 So I think we did see a need for this a lot

13:24.880 --> 13:30.000
 from the research perspective and early days of deep learning

13:30.000 --> 13:32.280
 in some ways.

13:32.280 --> 13:33.040
 41 million?

13:33.040 --> 13:37.640
 No, I don't think I imagine this number then.

13:37.640 --> 13:42.760
 It seemed like there's a potential future where lots more people

13:42.760 --> 13:43.760
 would be doing this.

13:43.760 --> 13:45.640
 And how do we enable that?

13:45.640 --> 13:49.560
 I would say this kind of growth, I probably

13:49.560 --> 13:53.680
 started seeing somewhat after the open sourcing where it was

13:53.680 --> 13:56.240
 like, OK, deep learning is actually

13:56.240 --> 13:59.200
 growing way faster for a lot of different reasons.

13:59.200 --> 14:02.720
 And we are in just the right place to push on that

14:02.720 --> 14:06.040
 and leverage that and deliver on lots of things

14:06.040 --> 14:07.440
 that people want.

14:07.440 --> 14:09.760
 So what changed once the open source?

14:09.760 --> 14:13.320
 Like how this incredible amount of attention

14:13.320 --> 14:16.120
 from a global population of developers,

14:16.120 --> 14:18.200
 how did the projects start changing?

14:18.200 --> 14:21.880
 I don't even actually remember it during those times.

14:21.880 --> 14:24.560
 I know looking now, there's really good documentation.

14:24.560 --> 14:26.560
 There's an ecosystem of tools.

14:26.560 --> 14:31.080
 There's a YouTube channel now.

14:31.080 --> 14:33.760
 It's very community driven.

14:33.760 --> 14:38.800
 Back then, I guess 0.1 version.

14:38.800 --> 14:39.760
 Is that the version?

14:39.760 --> 14:42.680
 I think we called it 0.6 or 5, something like that.

14:42.680 --> 14:43.720
 Something like that.

14:43.720 --> 14:47.200
 What changed leading into 1.0?

14:47.200 --> 14:48.480
 It's interesting.

14:48.480 --> 14:51.640
 I think we've gone through a few things there.

14:51.640 --> 14:53.680
 When we started out, when we first came out,

14:53.680 --> 14:56.080
 people loved the documentation we have.

14:56.080 --> 14:58.800
 Because it was just a huge step up from everything else.

14:58.800 --> 15:01.920
 Because all of those were academic projects, people

15:01.920 --> 15:04.560
 don't think about documentation.

15:04.560 --> 15:08.040
 I think what that changed was instead of deep learning

15:08.040 --> 15:12.560
 being a research thing, some people who were just developers

15:12.560 --> 15:15.080
 could now suddenly take this out and do

15:15.080 --> 15:16.920
 some interesting things with it.

15:16.920 --> 15:20.720
 Who had no clue what machine learning was before then.

15:20.720 --> 15:22.520
 And that, I think, really changed

15:22.520 --> 15:27.880
 how things started to scale up in some ways and pushed on it.

15:27.880 --> 15:30.400
 Over the next few months, as we looked at,

15:30.400 --> 15:31.960
 how do we stabilize things?

15:31.960 --> 15:33.840
 As we look at not just researchers,

15:33.840 --> 15:34.880
 now we want stability.

15:34.880 --> 15:36.480
 People want to deploy things.

15:36.480 --> 15:38.960
 That's how we started planning for 1.0.

15:38.960 --> 15:42.240
 And there are certain needs for that perspective.

15:42.240 --> 15:45.320
 And so, again, documentation comes up,

15:45.320 --> 15:49.480
 designs, more kinds of things to put that together.

15:49.480 --> 15:53.120
 And so that was exciting to get that to a stage where

15:53.120 --> 15:56.400
 more and more enterprises wanted to buy in and really

15:56.400 --> 15:58.720
 get behind that.

15:58.720 --> 16:02.640
 And I think post 1.0 and with the next few releases,

16:02.640 --> 16:05.240
 their enterprise adoption also started to take off.

16:05.240 --> 16:08.000
 I would say between the initial release and 1.0,

16:08.000 --> 16:11.000
 it was, OK, researchers, of course.

16:11.000 --> 16:13.720
 Then a lot of hobbies and early interest,

16:13.720 --> 16:15.920
 people excited about this who started to get on board.

16:15.920 --> 16:19.000
 And then over the 1.x thing, lots of enterprises.

16:19.000 --> 16:23.760
 I imagine anything that's below 1.0

16:23.760 --> 16:27.160
 gets pressured to be enterprise problem or something

16:27.160 --> 16:28.000
 that's stable.

16:28.000 --> 16:28.800
 Exactly.

16:28.800 --> 16:33.360
 And do you have a sense now that TensorFlow is stable?

16:33.360 --> 16:35.520
 It feels like deep learning, in general,

16:35.520 --> 16:37.800
 is extremely dynamic field.

16:37.800 --> 16:39.680
 So much is changing.

16:39.680 --> 16:43.400
 Do you have a, and TensorFlow has been growing incredibly.

16:43.400 --> 16:46.720
 Do you have a sense of stability at the helm of this?

16:46.720 --> 16:48.360
 I mean, I know you're in the midst of it.

16:48.360 --> 16:50.360
 Yeah.

16:50.360 --> 16:54.000
 I think in the midst of it, it's often easy to forget what

16:54.000 --> 16:58.160
 an enterprise wants and what some of the people on that side

16:58.160 --> 16:58.760
 want.

16:58.760 --> 17:00.360
 There are still people running models

17:00.360 --> 17:02.640
 that are three years old, four years old.

17:02.640 --> 17:06.000
 So inception is still used by tons of people.

17:06.000 --> 17:08.880
 Even less than 50 is what, a couple of years old now or more.

17:08.880 --> 17:12.200
 But there are tons of people who use that, and they're fine.

17:12.200 --> 17:16.200
 They don't need the last couple of bits of performance or quality.

17:16.200 --> 17:19.600
 They want some stability in things that just work.

17:19.600 --> 17:22.720
 And so there is value in providing that with that kind

17:22.720 --> 17:25.160
 of stability and making it really simpler,

17:25.160 --> 17:27.800
 because that allows a lot more people to access it.

17:27.800 --> 17:31.640
 And then there's the research crowd, which wants, OK,

17:31.640 --> 17:33.680
 they want to do these crazy things exactly like you're

17:33.680 --> 17:37.000
 saying, not just deep learning in the straight up models

17:37.000 --> 17:38.400
 that used to be there.

17:38.400 --> 17:41.920
 They want RNNs, and even RNNs are maybe old.

17:41.920 --> 17:45.520
 They are transformers now, and now it

17:45.520 --> 17:48.720
 needs to combine with RL and GANs and so on.

17:48.720 --> 17:52.160
 So there's definitely that area, the boundary that's

17:52.160 --> 17:55.120
 shifting and pushing the state of the art.

17:55.120 --> 17:57.120
 But I think there's more and more of the past

17:57.120 --> 17:59.680
 that's much more stable.

17:59.680 --> 18:02.680
 And even stuff that was two, three years old

18:02.680 --> 18:04.920
 is very, very usable by lots of people.

18:04.920 --> 18:07.440
 So that part makes it a lot easier.

18:07.440 --> 18:09.800
 So I imagine maybe you can correct me if I'm wrong.

18:09.800 --> 18:12.440
 One of the biggest use cases is essentially

18:12.440 --> 18:15.160
 taking something like ResNet 50 and doing

18:15.160 --> 18:18.520
 some kind of transfer learning on a very particular problem

18:18.520 --> 18:19.600
 that you have.

18:19.600 --> 18:24.480
 It's basically probably what majority of the world does.

18:24.480 --> 18:27.040
 And you want to make that as easy as possible.

18:27.040 --> 18:30.400
 So I would say, for the hobbyist perspective,

18:30.400 --> 18:32.800
 that's the most common case.

18:32.800 --> 18:34.800
 In fact, the apps on phones and stuff

18:34.800 --> 18:37.680
 that you'll see, the early ones, that's the most common case.

18:37.680 --> 18:40.320
 I would say there are a couple of reasons for that.

18:40.320 --> 18:44.400
 One is that everybody talks about that.

18:44.400 --> 18:46.120
 It looks great on slides.

18:46.120 --> 18:48.120
 That's a great presentation.

18:48.120 --> 18:50.040
 Exactly.

18:50.040 --> 18:53.120
 What enterprises want is that is part of it,

18:53.120 --> 18:54.480
 but that's not the big thing.

18:54.480 --> 18:56.760
 Enterprises really have data that they

18:56.760 --> 18:58.040
 want to make predictions on.

18:58.040 --> 19:01.160
 This is often what they used to do with the people who

19:01.160 --> 19:03.600
 were doing ML was just regression models,

19:03.600 --> 19:06.440
 linear regression, logistic regression, linear models,

19:06.440 --> 19:09.800
 or maybe gradient booster trees and so on.

19:09.800 --> 19:11.760
 Some of them still benefit from deep learning,

19:11.760 --> 19:14.440
 but they weren't that that's the bread and butter,

19:14.440 --> 19:16.280
 like the structured data and so on.

19:16.280 --> 19:18.200
 So depending on the audience you look at,

19:18.200 --> 19:19.520
 they're a little bit different.

19:19.520 --> 19:23.320
 And they just have, I mean, the best of enterprise

19:23.320 --> 19:26.480
 probably just has a very large data set

19:26.480 --> 19:28.640
 where deep learning can probably shine.

19:28.640 --> 19:29.360
 That's correct.

19:29.360 --> 19:30.320
 That's right.

19:30.320 --> 19:32.240
 And then I think the other pieces

19:32.240 --> 19:34.560
 that they wanted, again, to point out

19:34.560 --> 19:36.400
 that the developer summit we put together

19:36.400 --> 19:38.200
 is that the whole TensorFlow Extended

19:38.200 --> 19:40.600
 piece, which is the entire pipeline,

19:40.600 --> 19:43.560
 they care about stability across doing their entire thing.

19:43.560 --> 19:46.200
 They want simplicity across the entire thing.

19:46.200 --> 19:47.680
 I don't need to just train a model.

19:47.680 --> 19:51.280
 I need to do that every day again, over and over again.

19:51.280 --> 19:54.720
 I wonder to which degree you have a role in, I don't know.

19:54.720 --> 19:57.040
 So I teach a course on deep learning.

19:57.040 --> 20:01.320
 I have people like lawyers come up to me and say,

20:01.320 --> 20:04.200
 when is machine learning going to enter legal,

20:04.200 --> 20:05.560
 the legal realm?

20:05.560 --> 20:11.720
 The same thing in all kinds of disciplines, immigration,

20:11.720 --> 20:13.800
 insurance.

20:13.800 --> 20:17.400
 Often when I see what it boils down to is these companies

20:17.400 --> 20:19.760
 are often a little bit old school in the way

20:19.760 --> 20:20.840
 they organize the data.

20:20.840 --> 20:22.800
 So the data is just not ready yet.

20:22.800 --> 20:24.040
 It's not digitized.

20:24.040 --> 20:28.160
 Do you also find yourself being in the role of an evangelist

20:28.160 --> 20:33.040
 for let's organize your data, folks,

20:33.040 --> 20:35.440
 and then you'll get the big benefit of TensorFlow?

20:35.440 --> 20:38.000
 Do you have those conversations?

20:38.000 --> 20:45.160
 Yeah, I get all kinds of questions there from, OK,

20:45.160 --> 20:49.000
 what do I need to make this work, right?

20:49.000 --> 20:50.800
 Do we really need deep learning?

20:50.800 --> 20:52.240
 I mean, there are all these things.

20:52.240 --> 20:54.000
 I already used this linear model.

20:54.000 --> 20:55.160
 Why would this help?

20:55.160 --> 20:57.160
 I don't have enough data, let's say.

20:57.160 --> 20:59.960
 Or I want to use machine learning,

20:59.960 --> 21:01.760
 but I have no clue where to start.

21:01.760 --> 21:04.920
 So it's a great start to all the way to the experts

21:04.920 --> 21:08.520
 who wise were very specific things, so it's interesting.

21:08.520 --> 21:09.600
 Is there a good answer?

21:09.600 --> 21:12.480
 It boils down to oftentimes digitizing data.

21:12.480 --> 21:15.240
 So whatever you want automated, whatever data

21:15.240 --> 21:17.480
 you want to make prediction based on,

21:17.480 --> 21:21.240
 you have to make sure that it's in an organized form.

21:21.240 --> 21:23.920
 Like with an intensive flow ecosystem,

21:23.920 --> 21:26.080
 there's now you're providing more and more data

21:26.080 --> 21:28.960
 sets and more and more pretrained models.

21:28.960 --> 21:32.400
 Are you finding yourself also the organizer of data sets?

21:32.400 --> 21:34.480
 Yes, I think with TensorFlow data sets

21:34.480 --> 21:38.360
 that we just released, that's definitely come up where people

21:38.360 --> 21:39.200
 want these data sets.

21:39.200 --> 21:41.560
 Can we organize them and can we make that easier?

21:41.560 --> 21:45.320
 So that's definitely one important thing.

21:45.320 --> 21:47.680
 The other related thing I would say is I often tell people,

21:47.680 --> 21:50.960
 you know what, don't think of the most fanciest thing

21:50.960 --> 21:53.320
 that the newest model that you see.

21:53.320 --> 21:55.480
 Make something very basic work, and then

21:55.480 --> 21:56.360
 you can improve it.

21:56.360 --> 21:58.840
 There's just lots of things you can do with it.

21:58.840 --> 22:00.080
 Yeah, start with the basics.

22:00.080 --> 22:00.580
 Sure.

22:00.580 --> 22:03.760
 One of the big things that makes TensorFlow even more

22:03.760 --> 22:06.440
 accessible was the appearance, whenever

22:06.440 --> 22:12.400
 that happened, of Keras, the Keras standard outside of TensorFlow.

22:12.400 --> 22:18.200
 I think it was Keras on top of Tiano at first only,

22:18.200 --> 22:22.480
 and then Keras became on top of TensorFlow.

22:22.480 --> 22:29.840
 Do you know when Keras chose to also add TensorFlow as a back end,

22:29.840 --> 22:33.960
 who was it just the community that drove that initially?

22:33.960 --> 22:37.000
 Do you know if there was discussions, conversations?

22:37.000 --> 22:40.920
 Yeah, so Franco started the Keras project

22:40.920 --> 22:44.560
 before he was at Google, and the first thing was Tiano.

22:44.560 --> 22:47.120
 I don't remember if that was after TensorFlow

22:47.120 --> 22:49.640
 was created or way before.

22:49.640 --> 22:52.000
 And then at some point, when TensorFlow

22:52.000 --> 22:54.160
 started becoming popular, there were enough similarities

22:54.160 --> 22:56.320
 that he decided to create this interface

22:56.320 --> 22:59.200
 and put TensorFlow as a back end.

22:59.200 --> 23:03.320
 I believe that might still have been before he joined Google.

23:03.320 --> 23:06.720
 So we weren't really talking about that.

23:06.720 --> 23:09.720
 He decided on his own and thought that was interesting

23:09.720 --> 23:12.760
 and relevant to the community.

23:12.760 --> 23:17.080
 In fact, I didn't find out about him being at Google

23:17.080 --> 23:19.680
 until a few months after he was here.

23:19.680 --> 23:21.840
 He was working on some research ideas.

23:21.840 --> 23:24.480
 And doing Keras and his nights and weekends project and stuff.

23:24.480 --> 23:25.280
 I wish this thing.

23:25.280 --> 23:28.480
 So he wasn't part of the TensorFlow.

23:28.480 --> 23:29.680
 He didn't join initially.

23:29.680 --> 23:32.240
 He joined research, and he was doing some amazing research.

23:32.240 --> 23:35.440
 He has some papers on that and research.

23:35.440 --> 23:38.400
 He's a great researcher as well.

23:38.400 --> 23:42.400
 And at some point, we realized, oh, he's doing this good stuff.

23:42.400 --> 23:45.480
 People seem to like the API, and he's right here.

23:45.480 --> 23:48.280
 So we talked to him, and he said, OK,

23:48.280 --> 23:50.600
 why don't I come over to your team

23:50.600 --> 23:52.800
 and work with you for a quarter?

23:52.800 --> 23:55.440
 And let's make that integration happen.

23:55.440 --> 23:57.200
 And we talked to his manager, and he said, sure,

23:57.200 --> 23:59.720
 what, quarter's fine.

23:59.720 --> 24:03.320
 And that quarter's been something like two years now.

24:03.320 --> 24:05.040
 So he's fully on this.

24:05.040 --> 24:12.000
 So Keras got integrated into TensorFlow in a deep way.

24:12.000 --> 24:15.920
 And now with TensorFlow 2.0, Keras

24:15.920 --> 24:19.400
 is kind of the recommended way for a beginner

24:19.400 --> 24:21.960
 to interact with TensorFlow, which

24:21.960 --> 24:24.640
 makes that initial sort of transfer learning

24:24.640 --> 24:28.040
 or the basic use cases, even for an enterprise,

24:28.040 --> 24:29.320
 super simple, right?

24:29.320 --> 24:29.920
 That's correct.

24:29.920 --> 24:30.440
 That's right.

24:30.440 --> 24:32.040
 So what was that decision like?

24:32.040 --> 24:38.640
 That seems like it's kind of a bold decision as well.

24:38.640 --> 24:41.200
 We did spend a lot of time thinking about that one.

24:41.200 --> 24:46.000
 We had a bunch of APIs some bit by us.

24:46.000 --> 24:48.760
 There was a parallel layers API that we were building

24:48.760 --> 24:51.560
 and when we decided to do Keras in parallel,

24:51.560 --> 24:54.400
 so they were like, OK, two things that we are looking at.

24:54.400 --> 24:55.960
 And the first thing we was trying to do

24:55.960 --> 25:00.080
 is just have them look similar, be as integrated as possible,

25:00.080 --> 25:02.200
 share all of that stuff.

25:02.200 --> 25:05.800
 There were also three other APIs that others had built over time

25:05.800 --> 25:09.000
 because we didn't have a standard one.

25:09.000 --> 25:12.080
 But one of the messages that we kept hearing from the community,

25:12.080 --> 25:13.200
 OK, which one do we use?

25:13.200 --> 25:15.560
 And they kept seeing, OK, here's a model in this one,

25:15.560 --> 25:18.840
 and here's a model in this one, which should I pick?

25:18.840 --> 25:22.680
 So that's sort of like, OK, we had to address that

25:22.680 --> 25:24.000
 straight on with 2.0.

25:24.000 --> 25:26.320
 The whole idea was we need to simplify.

25:26.320 --> 25:28.600
 We had to pick one.

25:28.600 --> 25:34.600
 Based on where we were, we were like, OK, let's see what

25:34.600 --> 25:35.640
 are the people like.

25:35.640 --> 25:39.280
 And Keras was clearly one that lots of people loved.

25:39.280 --> 25:41.600
 There were lots of great things about it.

25:41.600 --> 25:43.880
 So we settled on that.

25:43.880 --> 25:44.680
 Organically.

25:44.680 --> 25:46.560
 That's kind of the best way to do it.

25:46.560 --> 25:47.160
 It was great.

25:47.160 --> 25:48.720
 But it was surprising, nevertheless,

25:48.720 --> 25:51.120
 to sort of bring in and outside.

25:51.120 --> 25:54.440
 I mean, there was a feeling like Keras might be almost

25:54.440 --> 25:58.000
 like a competitor in a certain kind of a two tensor flow.

25:58.000 --> 26:01.320
 And in a sense, it became an empowering element

26:01.320 --> 26:02.200
 of tensor flow.

26:02.200 --> 26:03.280
 That's right.

26:03.280 --> 26:07.200
 Yeah, it's interesting how you can put two things together

26:07.200 --> 26:08.280
 which can align right.

26:08.280 --> 26:11.760
 And in this case, I think Francois, the team,

26:11.760 --> 26:15.480
 and a bunch of us have chatted and I think we all

26:15.480 --> 26:17.320
 want to see the same kind of things.

26:17.320 --> 26:20.360
 We all care about making it easier for the huge set

26:20.360 --> 26:21.440
 of developers out there.

26:21.440 --> 26:23.440
 And that makes a difference.

26:23.440 --> 26:27.280
 So Python has Guido van Rossum, who

26:27.280 --> 26:30.320
 until recently held the position of benevolent

26:30.320 --> 26:31.960
 dictator for life.

26:31.960 --> 26:36.040
 Right, so there's a huge successful open source

26:36.040 --> 26:37.320
 project like tensor flow.

26:37.320 --> 26:40.680
 Need one person who makes a final decision.

26:40.680 --> 26:45.480
 So you did a pretty successful tensor flow Dev Summit

26:45.480 --> 26:47.520
 just now, last couple of days.

26:47.520 --> 26:51.080
 There's clearly a lot of different new features

26:51.080 --> 26:55.480
 being incorporated in amazing ecosystem, so on.

26:55.480 --> 26:57.320
 How are those design decisions made?

26:57.320 --> 27:00.960
 Is there a BDFL in tensor flow?

27:00.960 --> 27:05.800
 And or is it more distributed and organic?

27:05.800 --> 27:09.880
 I think it's somewhat different, I would say.

27:09.880 --> 27:16.160
 I've always been involved in the key design directions.

27:16.160 --> 27:17.560
 But there are lots of things that

27:17.560 --> 27:20.960
 are distributed where their number of people, Martin

27:20.960 --> 27:24.760
 Wick being one who has really driven a lot of our open source

27:24.760 --> 27:27.360
 stuff, a lot of the APIs.

27:27.360 --> 27:29.200
 And there are a number of other people

27:29.200 --> 27:32.720
 who have been pushed and been responsible

27:32.720 --> 27:35.240
 for different parts of it.

27:35.240 --> 27:37.840
 We do have regular design reviews.

27:37.840 --> 27:40.680
 Over the last year, we've really spent a lot of time opening up

27:40.680 --> 27:44.160
 to the community and adding transparency.

27:44.160 --> 27:45.880
 We're setting more processes in place,

27:45.880 --> 27:49.600
 so RFCs, special interest groups, really

27:49.600 --> 27:53.560
 grow that community and scale that.

27:53.560 --> 27:57.680
 I think the kind of scale that ecosystem is in,

27:57.680 --> 28:00.240
 I don't think we could scale with having me as the lone

28:00.240 --> 28:02.320
 point of decision maker.

28:02.320 --> 28:03.440
 I got it.

28:03.440 --> 28:05.880
 So yeah, the growth of that ecosystem,

28:05.880 --> 28:08.040
 maybe you can talk about it a little bit.

28:08.040 --> 28:10.720
 First of all, when I started with Andre Karpathi

28:10.720 --> 28:13.640
 when he first did ComNet.js, the fact

28:13.640 --> 28:15.360
 that you can train in your own network

28:15.360 --> 28:18.480
 and the browser in JavaScript was incredible.

28:18.480 --> 28:21.000
 So now TensorFlow.js is really making

28:21.000 --> 28:26.920
 that a serious, a legit thing, a way

28:26.920 --> 28:29.560
 to operate, whether it's in the back end or the front end.

28:29.560 --> 28:32.720
 Then there's the TensorFlow Extended, like you mentioned.

28:32.720 --> 28:35.360
 There's TensorFlow Lite for mobile.

28:35.360 --> 28:37.480
 And all of it, as far as I can tell,

28:37.480 --> 28:39.640
 it's really converging towards being

28:39.640 --> 28:43.440
 able to save models in the same kind of way.

28:43.440 --> 28:46.680
 You can move around, you can train on the desktop,

28:46.680 --> 28:48.800
 and then move it to mobile, and so on.

28:48.800 --> 28:49.280
 That's right.

28:49.280 --> 28:52.320
 So this is that cohesiveness.

28:52.320 --> 28:55.240
 So can you maybe give me whatever

28:55.240 --> 28:58.840
 I missed, a bigger overview of the mission of the ecosystem

28:58.840 --> 29:02.120
 that's trying to be built, and where is it moving forward?

29:02.120 --> 29:02.800
 Yeah.

29:02.800 --> 29:05.720
 So in short, the way I like to think of this

29:05.720 --> 29:09.760
 is our goals to enable machine learning.

29:09.760 --> 29:13.320
 And in a couple of ways, one is we

29:13.320 --> 29:16.560
 have lots of exciting things going on in ML today.

29:16.560 --> 29:18.160
 We started with deep learning, but we now

29:18.160 --> 29:21.400
 support a bunch of other algorithms too.

29:21.400 --> 29:23.760
 So one is to, on the research side,

29:23.760 --> 29:25.360
 keep pushing on the state of the art.

29:25.360 --> 29:27.240
 Can we, how do we enable researchers

29:27.240 --> 29:28.960
 to build the next amazing thing?

29:28.960 --> 29:31.800
 So BERT came out recently.

29:31.800 --> 29:34.000
 It's great that people are able to do new kinds of research.

29:34.000 --> 29:35.400
 There are lots of amazing research

29:35.400 --> 29:37.600
 that happens across the world.

29:37.600 --> 29:38.880
 So that's one direction.

29:38.880 --> 29:41.400
 The other is, how do you take that

29:41.400 --> 29:45.200
 across all the people outside who want to take that research

29:45.200 --> 29:47.400
 and do some great things with it and integrate it

29:47.400 --> 29:51.800
 to build real products, to have a real impact on people?

29:51.800 --> 29:56.720
 And so if that's the other axes in some ways.

29:56.720 --> 29:58.520
 And a high level, one way I think about it

29:58.520 --> 30:02.480
 is there are a crazy number of computer devices

30:02.480 --> 30:04.240
 across the world.

30:04.240 --> 30:08.440
 And we often used to think of ML and training and all of this

30:08.440 --> 30:10.800
 as, OK, something you do either in the workstation

30:10.800 --> 30:13.600
 or the data center or cloud.

30:13.600 --> 30:15.720
 But we see things running on the phones.

30:15.720 --> 30:17.640
 We see things running on really tiny chips.

30:17.640 --> 30:20.760
 And we had some demos at the developer summit.

30:20.760 --> 30:25.160
 And so the way I think about this ecosystem

30:25.160 --> 30:30.280
 is, how do we help get machine learning on every device that

30:30.280 --> 30:32.520
 has a compute capability?

30:32.520 --> 30:33.760
 And that continues to grow.

30:33.760 --> 30:37.240
 And so in some ways, this ecosystem

30:37.240 --> 30:40.280
 has looked at various aspects of that

30:40.280 --> 30:42.440
 and grown over time to cover more of those.

30:42.440 --> 30:44.640
 And we continue to push the boundaries.

30:44.640 --> 30:48.640
 In some areas, we've built more tooling and things

30:48.640 --> 30:50.040
 around that to help you.

30:50.040 --> 30:52.800
 I mean, the first tool we started was TensorBoard.

30:52.800 --> 30:56.920
 You want to learn just the training piece, the effects

30:56.920 --> 30:59.840
 for TensorFlow Extended to really do your entire ML

30:59.840 --> 31:04.760
 pipelines if you care about all that production stuff,

31:04.760 --> 31:09.520
 but then going to the edge, going to different kinds of things.

31:09.520 --> 31:11.800
 And it's not just us now.

31:11.800 --> 31:15.120
 We are a place where there are lots of libraries being built

31:15.120 --> 31:15.840
 on top.

31:15.840 --> 31:18.440
 So there are some for research, maybe things

31:18.440 --> 31:21.240
 like TensorFlow Agents or TensorFlow Probability that

31:21.240 --> 31:23.480
 started as research things or for researchers

31:23.480 --> 31:26.160
 for focusing on certain kinds of algorithms,

31:26.160 --> 31:30.280
 but they're also being deployed or reduced by production folks.

31:30.280 --> 31:34.000
 And some have come from within Google, just teams

31:34.000 --> 31:37.040
 across Google who wanted to do the build these things.

31:37.040 --> 31:39.680
 Others have come from just the community

31:39.680 --> 31:41.840
 because there are different pieces

31:41.840 --> 31:44.640
 that different parts of the community care about.

31:44.640 --> 31:49.520
 And I see our goal as enabling even that.

31:49.520 --> 31:53.240
 It's not we cannot and won't build every single thing.

31:53.240 --> 31:54.840
 That just doesn't make sense.

31:54.840 --> 31:57.320
 But if we can enable others to build the things

31:57.320 --> 32:00.640
 that they care about, and there's a broader community that

32:00.640 --> 32:02.880
 cares about that, and we can help encourage that,

32:02.880 --> 32:05.240
 and that's great.

32:05.240 --> 32:08.600
 That really helps the entire ecosystem, not just those.

32:08.600 --> 32:11.280
 One of the big things about 2.0 that we're pushing on

32:11.280 --> 32:14.680
 is, OK, we have these so many different pieces, right?

32:14.680 --> 32:18.440
 How do we help make all of them work well together?

32:18.440 --> 32:21.960
 There are a few key pieces there that we're pushing on,

32:21.960 --> 32:23.840
 one being the core format in there

32:23.840 --> 32:27.480
 and how we share the models themselves through SAVE model

32:27.480 --> 32:30.440
 and what TensorFlow Hub and so on.

32:30.440 --> 32:34.000
 And a few of the pieces that we really put this together.

32:34.000 --> 32:37.240
 I was very skeptical that that's, when TensorFlow.js came out,

32:37.240 --> 32:40.120
 it didn't seem or deep learning.js.

32:40.120 --> 32:41.680
 Yeah, that was the first.

32:41.680 --> 32:45.040
 It seems like technically very difficult project.

32:45.040 --> 32:47.040
 As a standalone, it's not as difficult.

32:47.040 --> 32:49.920
 But as a thing that integrates into the ecosystem,

32:49.920 --> 32:51.240
 it seems very difficult.

32:51.240 --> 32:53.200
 So I mean, there's a lot of aspects of this

32:53.200 --> 32:54.200
 you're making look easy.

32:54.200 --> 32:58.160
 But on the technical side, how many challenges

32:58.160 --> 33:00.560
 have to be overcome here?

33:00.560 --> 33:01.520
 A lot.

33:01.520 --> 33:03.080
 And still have to be overcome.

33:03.080 --> 33:04.840
 That's the question here, too.

33:04.840 --> 33:06.160
 There are lots of steps to it.

33:06.160 --> 33:08.160
 I think we've iterated over the last few years,

33:08.160 --> 33:10.720
 so there's a lot we've learned.

33:10.720 --> 33:14.200
 I, yeah, and often when things come together well,

33:14.200 --> 33:15.080
 things look easy.

33:15.080 --> 33:16.400
 And that's exactly the point.

33:16.400 --> 33:18.280
 It should be easy for the end user.

33:18.280 --> 33:21.320
 But there are lots of things that go behind that.

33:21.320 --> 33:25.320
 If I think about still challenges ahead,

33:25.320 --> 33:32.880
 there are we have a lot more devices coming on board,

33:32.880 --> 33:35.280
 for example, from the hardware perspective.

33:35.280 --> 33:37.640
 How do we make it really easy for these vendors

33:37.640 --> 33:42.040
 to integrate with something like TensorFlow?

33:42.040 --> 33:43.640
 So there's a lot of compiler stuff

33:43.640 --> 33:45.320
 that others are working on.

33:45.320 --> 33:48.320
 There are things we can do in terms of our APIs

33:48.320 --> 33:50.520
 and so on that we can do.

33:50.520 --> 33:55.840
 As we, TensorFlow started as a very monolithic system.

33:55.840 --> 33:57.680
 And to some extent, it still is.

33:57.680 --> 33:59.400
 There are less lots of tools around it,

33:59.400 --> 34:02.960
 but the core is still pretty large and monolithic.

34:02.960 --> 34:05.760
 One of the key challenges for us to scale that out

34:05.760 --> 34:10.440
 is how do we break that apart with clear interfaces?

34:10.440 --> 34:13.720
 It's, in some ways, it's software engineering one

34:13.720 --> 34:18.520
 one, but for a system that's now four years old, I guess,

34:18.520 --> 34:21.600
 or more, and that's still rapidly evolving

34:21.600 --> 34:24.000
 and that we're not slowing down with,

34:24.000 --> 34:28.240
 it's hard to change and modify and really break apart.

34:28.240 --> 34:29.880
 It's sort of like, as people say, right,

34:29.880 --> 34:32.560
 it's like changing the engine with a car running

34:32.560 --> 34:33.560
 or fixed benefits.

34:33.560 --> 34:35.200
 That's exactly what we're trying to do.

34:35.200 --> 34:39.960
 So there's a challenge here, because the downside

34:39.960 --> 34:43.840
 of so many people being excited about TensorFlow

34:43.840 --> 34:48.600
 and becoming to rely on it in many other applications

34:48.600 --> 34:52.200
 is that you're kind of responsible.

34:52.200 --> 34:53.520
 It's the technical debt.

34:53.520 --> 34:55.640
 You're responsible for previous versions

34:55.640 --> 34:57.720
 to some degree still working.

34:57.720 --> 34:59.920
 So when you're trying to innovate,

34:59.920 --> 35:03.760
 I mean, it's probably easier to just start from scratch

35:03.760 --> 35:05.800
 every few months.

35:05.800 --> 35:07.160
 Absolutely.

35:07.160 --> 35:10.880
 So do you feel the pain of that?

35:10.880 --> 35:15.360
 2.0 does break some back compatibility, but not too much.

35:15.360 --> 35:18.120
 It seems like the conversion is pretty straightforward.

35:18.120 --> 35:20.240
 Do you think that's still important,

35:20.240 --> 35:22.880
 given how quickly deep learning is changing?

35:22.880 --> 35:26.360
 Can you just, the things that you've learned,

35:26.360 --> 35:27.440
 can you just start over?

35:27.440 --> 35:30.120
 Or is there pressure to not?

35:30.120 --> 35:31.640
 It's a tricky balance.

35:31.640 --> 35:36.840
 So if it was just a researcher writing a paper who

35:36.840 --> 35:39.400
 a year later will not look at that code again,

35:39.400 --> 35:41.560
 sure, it doesn't matter.

35:41.560 --> 35:43.440
 There are a lot of production systems

35:43.440 --> 35:45.480
 that rely on TensorFlow, both at Google

35:45.480 --> 35:47.240
 and across the world.

35:47.240 --> 35:49.760
 And people worry about this.

35:49.760 --> 35:53.400
 I mean, these systems run for a long time.

35:53.400 --> 35:57.240
 So it is important to keep that compatibility and so on.

35:57.240 --> 36:00.960
 And yes, it does come with a huge cost.

36:00.960 --> 36:02.920
 We have to think about a lot of things

36:02.920 --> 36:06.960
 as we do new things and make new changes.

36:06.960 --> 36:09.120
 I think it's a trade off, right?

36:09.120 --> 36:12.960
 You can, you might slow certain kinds of things down,

36:12.960 --> 36:15.440
 but the overall value you're bringing because of that

36:15.440 --> 36:18.440
 is much bigger because it's not just

36:18.440 --> 36:20.520
 about breaking the person yesterday.

36:20.520 --> 36:24.840
 It's also about telling the person tomorrow that, you know what?

36:24.840 --> 36:26.320
 This is how we do things.

36:26.320 --> 36:28.520
 We're not going to break you when you come on board

36:28.520 --> 36:30.320
 because there are lots of new people who are also

36:30.320 --> 36:32.880
 going to come on board.

36:32.880 --> 36:34.680
 So one way I like to think about this,

36:34.680 --> 36:37.960
 and I always push the team to think about it as well,

36:37.960 --> 36:39.640
 when you want to do new things, you

36:39.640 --> 36:42.000
 want to start with a clean slate,

36:42.000 --> 36:44.880
 design with a clean slate in mind,

36:44.880 --> 36:48.160
 and then we'll figure out how to make sure all the other things

36:48.160 --> 36:48.640
 work.

36:48.640 --> 36:52.160
 And yes, we do make compromises occasionally.

36:52.160 --> 36:55.200
 But unless you design with the clean slate

36:55.200 --> 36:58.400
 and not worry about that, you'll never get to a good place.

36:58.400 --> 36:59.120
 That's brilliant.

36:59.120 --> 37:04.080
 So even if you are responsible in the idea stage,

37:04.080 --> 37:07.680
 when you're thinking of new, just put all that behind you.

37:07.680 --> 37:09.600
 OK, that's really well put.

37:09.600 --> 37:12.480
 So I have to ask this because a lot of students, developers,

37:12.480 --> 37:16.280
 asked me how I feel about PyTorch versus TensorFlow.

37:16.280 --> 37:19.720
 So I've recently completely switched my research group

37:19.720 --> 37:20.920
 to TensorFlow.

37:20.920 --> 37:23.280
 I wish everybody would just use the same thing.

37:23.280 --> 37:26.960
 And TensorFlow is as close to that, I believe, as we have.

37:26.960 --> 37:32.000
 But do you enjoy competition?

37:32.000 --> 37:35.800
 So TensorFlow is leading in many ways, many dimensions

37:35.800 --> 37:39.000
 in terms of the ecosystem, in terms of the number of users,

37:39.000 --> 37:41.200
 momentum power, production level, so on.

37:41.200 --> 37:46.000
 But a lot of researchers are now also using PyTorch.

37:46.000 --> 37:47.520
 Do you enjoy that kind of competition,

37:47.520 --> 37:49.440
 or do you just ignore it and focus

37:49.440 --> 37:52.320
 on making TensorFlow the best that it can be?

37:52.320 --> 37:55.480
 So just like research or anything people are doing,

37:55.480 --> 37:58.120
 it's great to get different kinds of ideas.

37:58.120 --> 38:01.440
 And when we started with TensorFlow,

38:01.440 --> 38:05.480
 like I was saying earlier, it was very important for us

38:05.480 --> 38:07.440
 to also have production in mind.

38:07.440 --> 38:08.960
 We didn't want just research, right?

38:08.960 --> 38:11.280
 And that's why we chose certain things.

38:11.280 --> 38:13.480
 Now PyTorch came along and said, you know what?

38:13.480 --> 38:14.880
 I only care about research.

38:14.880 --> 38:16.320
 This is what I'm trying to do.

38:16.320 --> 38:18.400
 What's the best thing I can do for this?

38:18.400 --> 38:21.120
 And it started iterating and said, OK,

38:21.120 --> 38:22.520
 I don't need to worry about graphs.

38:22.520 --> 38:25.200
 Let me just run things.

38:25.200 --> 38:27.440
 I don't care if it's not as fast as it can be,

38:27.440 --> 38:30.480
 but let me just make this part easy.

38:30.480 --> 38:32.560
 And there are things you can learn from that, right?

38:32.560 --> 38:36.720
 They, again, had the benefit of seeing what had come before,

38:36.720 --> 38:40.520
 but also exploring certain different kinds of spaces.

38:40.520 --> 38:43.560
 And they had some good things there,

38:43.560 --> 38:46.680
 building on, say, things like Jainer and so on before that.

38:46.680 --> 38:49.320
 So competition is definitely interesting.

38:49.320 --> 38:51.040
 It made us, you know, this is an area

38:51.040 --> 38:53.720
 that we had thought about, like I said, very early on.

38:53.720 --> 38:56.600
 Over time, we had revisited this a couple of times.

38:56.600 --> 38:59.000
 Should we add this again?

38:59.000 --> 39:00.480
 At some point, we said, you know what,

39:00.480 --> 39:02.920
 here's it seems like this can be done well.

39:02.920 --> 39:04.280
 So let's try it again.

39:04.280 --> 39:07.680
 And that's how we started pushing on eager execution.

39:07.680 --> 39:09.880
 How do we combine those two together,

39:09.880 --> 39:13.080
 which has finally come very well together in 2.0,

39:13.080 --> 39:15.720
 but it took us a while to get all the things together

39:15.720 --> 39:16.320
 and so on.

39:16.320 --> 39:19.320
 So let me, I mean, ask, put another way.

39:19.320 --> 39:21.800
 I think eager execution is a really powerful thing,

39:21.800 --> 39:22.680
 those added.

39:22.680 --> 39:24.320
 Do you think he wouldn't have been,

39:25.840 --> 39:28.400
 you know, Muhammad Ali versus Frazier, right?

39:28.400 --> 39:31.200
 Do you think it wouldn't have been added as quickly

39:31.200 --> 39:33.760
 if PyTorch wasn't there?

39:33.760 --> 39:35.440
 It might have taken longer.

39:35.440 --> 39:36.280
 No longer.

39:36.280 --> 39:38.960
 It was, I mean, we had tried some variants of that before.

39:38.960 --> 39:40.920
 So I'm sure it would have happened,

39:40.920 --> 39:42.240
 but it might have taken longer.

39:42.240 --> 39:44.800
 I'm grateful that TensorFlow is part of the way they did.

39:44.800 --> 39:47.760
 That's doing some incredible work last couple of years.

39:47.760 --> 39:49.640
 What other things that we didn't talk about?

39:49.640 --> 39:51.520
 Are you looking forward in 2.0?

39:51.520 --> 39:54.040
 That comes to mind.

39:54.040 --> 39:56.520
 So we talked about some of the ecosystem stuff,

39:56.520 --> 40:01.440
 making it easily accessible to Keras, eager execution.

40:01.440 --> 40:02.880
 Is there other things that we missed?

40:02.880 --> 40:07.480
 Yeah, so I would say one is just where 2.0 is,

40:07.480 --> 40:10.760
 and, you know, with all the things that we've talked about,

40:10.760 --> 40:13.760
 I think as we think beyond that,

40:13.760 --> 40:16.640
 there are lots of other things that it enables us to do

40:16.640 --> 40:18.760
 and that we're excited about.

40:18.760 --> 40:20.720
 So what it's setting us up for,

40:20.720 --> 40:22.520
 okay, here are these really clean APIs.

40:22.520 --> 40:25.640
 We've cleaned up the surface for what the users want.

40:25.640 --> 40:28.320
 What it also allows us to do a whole bunch of stuff

40:28.320 --> 40:31.600
 behind the scenes once we are ready with 2.0.

40:31.600 --> 40:36.600
 So for example, in TensorFlow with graphs

40:36.760 --> 40:37.720
 and all the things you could do,

40:37.720 --> 40:40.600
 you could always get a lot of good performance

40:40.600 --> 40:43.280
 if you spent the time to tune it, right?

40:43.280 --> 40:47.720
 And we've clearly shown that, lots of people do that.

40:47.720 --> 40:52.720
 With 2.0, with these APIs where we are,

40:53.040 --> 40:55.120
 we can give you a lot of performance

40:55.120 --> 40:57.040
 just with whatever you do.

40:57.040 --> 41:01.400
 You know, because we see these, it's much cleaner.

41:01.400 --> 41:03.720
 We know most people are gonna do things this way.

41:03.720 --> 41:05.520
 We can really optimize for that

41:05.520 --> 41:09.040
 and get a lot of those things out of the box.

41:09.040 --> 41:10.400
 And it really allows us, you know,

41:10.400 --> 41:13.880
 both for single machine and distributed and so on,

41:13.880 --> 41:17.200
 to really explore other spaces behind the scenes

41:17.200 --> 41:19.680
 after 2.0 in the future versions as well.

41:19.680 --> 41:23.000
 So right now, the team's really excited about that,

41:23.000 --> 41:25.800
 that over time, I think we'll see that.

41:25.800 --> 41:27.720
 The other piece that I was talking about

41:27.720 --> 41:31.600
 in terms of just restructuring the monolithic thing

41:31.600 --> 41:34.320
 into more pieces and making it more modular,

41:34.320 --> 41:36.800
 I think that's gonna be really important

41:36.800 --> 41:41.800
 for a lot of the other people in the ecosystem,

41:41.800 --> 41:44.760
 other organizations and so on that wanted to build things.

41:44.760 --> 41:46.360
 Can you elaborate a little bit what you mean

41:46.360 --> 41:50.680
 by making TensorFlow more ecosystem or modular?

41:50.680 --> 41:55.000
 So the way it's organized today is there's one,

41:55.000 --> 41:56.280
 there are lots of repositories

41:56.280 --> 41:58.320
 in the TensorFlow organization at GitHub,

41:58.320 --> 42:01.080
 the core one where we have TensorFlow,

42:01.080 --> 42:04.080
 it has the execution engine,

42:04.080 --> 42:08.280
 it has, you know, the key backends for CPUs and GPUs,

42:08.280 --> 42:12.560
 it has the work to do distributed stuff.

42:12.560 --> 42:14.360
 And all of these just work together

42:14.360 --> 42:17.240
 in a single library or binary,

42:17.240 --> 42:18.800
 there's no way to split them apart easily.

42:18.800 --> 42:19.960
 I mean, there are some interfaces,

42:19.960 --> 42:21.600
 but they're not very clean.

42:21.600 --> 42:24.800
 In a perfect world, you would have clean interfaces where,

42:24.800 --> 42:27.720
 okay, I wanna run it on my fancy cluster

42:27.720 --> 42:29.360
 with some custom networking,

42:29.360 --> 42:30.960
 just implement this and do that.

42:30.960 --> 42:32.640
 I mean, we kind of support that,

42:32.640 --> 42:34.560
 but it's hard for people today.

42:35.480 --> 42:38.160
 I think as we are starting to see more interesting things

42:38.160 --> 42:39.400
 in some of these spaces,

42:39.400 --> 42:42.280
 having that clean separation will really start to help.

42:42.280 --> 42:47.280
 And again, going to the large size of the ecosystem

42:47.360 --> 42:50.120
 and the different groups involved there,

42:50.120 --> 42:53.440
 enabling people to evolve and push on things

42:53.440 --> 42:56.040
 more independently just allows it to scale better.

42:56.040 --> 42:59.080
 And by people, you mean individual developers and?

42:59.080 --> 42:59.920
 And organizations.

42:59.920 --> 43:00.920
 And organizations.

43:00.920 --> 43:01.760
 That's right.

43:01.760 --> 43:04.200
 So the hope is that everybody sort of major,

43:04.200 --> 43:06.880
 I don't know, Pepsi or something uses,

43:06.880 --> 43:11.040
 like major corporations go to TensorFlow to this kind of.

43:11.040 --> 43:13.640
 Yeah, if you look at enterprise like Pepsi or these,

43:13.640 --> 43:15.520
 I mean, a lot of them are already using TensorFlow.

43:15.520 --> 43:18.960
 They are not the ones that do the development

43:18.960 --> 43:20.360
 or changes in the core.

43:20.360 --> 43:21.920
 Some of them do, but a lot of them don't.

43:21.920 --> 43:23.720
 I mean, they touch small pieces.

43:23.720 --> 43:26.400
 There are lots of these, some of them being,

43:26.400 --> 43:28.200
 let's say hardware vendors who are building

43:28.200 --> 43:30.840
 their custom hardware and they want their own pieces.

43:30.840 --> 43:34.160
 Or some of them being bigger companies, say IBM.

43:34.160 --> 43:37.320
 I mean, they're involved in some of our special interest

43:37.320 --> 43:39.960
 groups and they see a lot of users

43:39.960 --> 43:42.640
 who want certain things and they want to optimize for that.

43:42.640 --> 43:44.480
 So folks like that often.

43:44.480 --> 43:46.400
 Autonomous vehicle companies, perhaps.

43:46.400 --> 43:48.200
 Exactly, yes.

43:48.200 --> 43:50.520
 So yeah, like I mentioned, TensorFlow

43:50.520 --> 43:54.120
 has been down on it 41 million times, 50,000 commits,

43:54.120 --> 43:58.360
 almost 10,000 pull requests, 1,800 contributors.

43:58.360 --> 44:02.160
 So I'm not sure if you can explain it,

44:02.160 --> 44:06.840
 but what does it take to build a community like that?

44:06.840 --> 44:09.200
 In retrospect, what do you think?

44:09.200 --> 44:12.080
 What is the critical thing that allowed for this growth

44:12.080 --> 44:14.600
 to happen and how does that growth continue?

44:14.600 --> 44:17.920
 Yeah, that's an interesting question.

44:17.920 --> 44:20.240
 I wish I had all the answers there, I guess,

44:20.240 --> 44:22.520
 so you could replicate it.

44:22.520 --> 44:25.520
 I think there are a number of things

44:25.520 --> 44:27.880
 that need to come together, right?

44:27.880 --> 44:33.720
 One, just like any new thing, there's

44:33.720 --> 44:37.960
 a sweet spot of timing, what's needed,

44:37.960 --> 44:39.520
 does it grow with what's needed.

44:39.520 --> 44:41.960
 So in this case, for example, TensorFlow

44:41.960 --> 44:43.640
 is not just grown because it has a good tool,

44:43.640 --> 44:46.640
 it's also grown with the growth of deep learning itself.

44:46.640 --> 44:49.000
 So those factors come into play.

44:49.000 --> 44:53.120
 Other than that, though, I think just

44:53.120 --> 44:55.560
 hearing, listening to the community, what they're

44:55.560 --> 44:58.400
 doing, what they need, being open to,

44:58.400 --> 45:01.080
 like in terms of external contributions,

45:01.080 --> 45:04.520
 we've spent a lot of time in making sure

45:04.520 --> 45:06.840
 we can accept those contributions well,

45:06.840 --> 45:09.400
 we can help the contributors in adding those,

45:09.400 --> 45:11.240
 putting the right process in place,

45:11.240 --> 45:13.320
 getting the right kind of community,

45:13.320 --> 45:16.120
 welcoming them, and so on.

45:16.120 --> 45:19.000
 Like over the last year, we've really pushed on transparency.

45:19.000 --> 45:22.200
 That's important for an open source project.

45:22.200 --> 45:23.760
 People want to know where things are going,

45:23.760 --> 45:26.400
 and we're like, OK, here's a process for you.

45:26.400 --> 45:29.320
 You can do that, here are our seasons, and so on.

45:29.320 --> 45:32.880
 So thinking through, there are lots of community aspects

45:32.880 --> 45:36.400
 that come into that you can really work on.

45:36.400 --> 45:38.720
 As a small project, it's maybe easy to do,

45:38.720 --> 45:42.240
 because there's two developers, and you can do those.

45:42.240 --> 45:46.960
 As you grow, putting more of these processes in place,

45:46.960 --> 45:49.080
 thinking about the documentation,

45:49.080 --> 45:51.400
 thinking about what two developers

45:51.400 --> 45:55.080
 care about, what kind of tools would they want to use,

45:55.080 --> 45:56.840
 all of these come into play, I think.

45:56.840 --> 45:58.400
 So one of the big things, I think,

45:58.400 --> 46:02.560
 that feeds the TensorFlow fire is people building something

46:02.560 --> 46:07.680
 on TensorFlow, and implement a particular architecture

46:07.680 --> 46:09.480
 that does something cool and useful,

46:09.480 --> 46:11.080
 and they put that on GitHub.

46:11.080 --> 46:15.640
 And so it just feeds this growth.

46:15.640 --> 46:19.560
 Do you have a sense that with 2.0 and 1.0,

46:19.560 --> 46:21.880
 that there may be a little bit of a partitioning like there

46:21.880 --> 46:26.040
 is with Python 2 and 3, that there'll be a code base

46:26.040 --> 46:28.320
 in the older versions of TensorFlow

46:28.320 --> 46:31.120
 that will not be as compatible easily,

46:31.120 --> 46:35.600
 or are you pretty confident that this kind of conversion

46:35.600 --> 46:37.960
 is pretty natural and easy to do?

46:37.960 --> 46:41.480
 So we're definitely working hard to make that very easy to do.

46:41.480 --> 46:44.040
 There's lots of tooling that we talked about at the developer

46:44.040 --> 46:46.480
 summit this week, and we'll continue

46:46.480 --> 46:48.280
 to invest in that tooling.

46:48.280 --> 46:52.560
 It's when you think of these significant version changes,

46:52.560 --> 46:55.720
 that's always a risk, and we are really pushing hard

46:55.720 --> 46:59.160
 to make that transition very, very smooth.

46:59.160 --> 47:03.000
 I think, so at some level, people

47:03.000 --> 47:05.520
 want to move when they see the value in the new thing.

47:05.520 --> 47:07.640
 They don't want to move just because it's a new thing.

47:07.640 --> 47:11.400
 And some people do, but most people want a really good thing.

47:11.400 --> 47:13.760
 And I think over the next few months,

47:13.760 --> 47:15.400
 as people start to see the value,

47:15.400 --> 47:17.640
 we'll definitely see that shift happening.

47:17.640 --> 47:20.080
 So I'm pretty excited and confident that we

47:20.080 --> 47:22.440
 will see people moving.

47:22.440 --> 47:24.680
 As you said earlier, this field is also moving rapidly,

47:24.680 --> 47:26.720
 so that'll help because we can do more things.

47:26.720 --> 47:28.520
 And all the new things will clearly

47:28.520 --> 47:32.280
 happen in 2.x, so people will have lots of good reasons to move.

47:32.280 --> 47:36.160
 So what do you think TensorFlow 3.0 looks like?

47:36.160 --> 47:40.320
 Is there things happening so crazily

47:40.320 --> 47:42.520
 that even at the end of this year,

47:42.520 --> 47:45.320
 seems impossible to plan for?

47:45.320 --> 47:49.440
 Or is it possible to plan for the next five years?

47:49.440 --> 47:50.800
 I think it's tricky.

47:50.800 --> 47:55.760
 There are some things that we can expect in terms of, OK,

47:55.760 --> 47:59.720
 change, yes, change is going to happen.

47:59.720 --> 48:01.680
 Are there some things going to stick around

48:01.680 --> 48:03.720
 and some things not going to stick around?

48:03.720 --> 48:08.160
 I would say the basics of deep learning,

48:08.160 --> 48:12.680
 the convolutional models or the basic kind of things,

48:12.680 --> 48:16.280
 they'll probably be around in some form still in five years.

48:16.280 --> 48:21.160
 Will Aurel and Gans stay very likely based on where they are?

48:21.160 --> 48:22.840
 Will we have new things?

48:22.840 --> 48:24.680
 Probably, but those are hard to predict.

48:24.680 --> 48:29.080
 And some directionally, some things that we can see

48:29.080 --> 48:32.800
 is in things that we're starting to do

48:32.800 --> 48:36.560
 with some of our projects right now is just

48:36.560 --> 48:39.120
 to point out combining eager execution and graphs,

48:39.120 --> 48:42.240
 where we're starting to make it more like just your natural

48:42.240 --> 48:43.160
 programming language.

48:43.160 --> 48:45.640
 You're not trying to program something else.

48:45.640 --> 48:47.240
 Similarly, with Swift for TensorFlow,

48:47.240 --> 48:48.280
 we're taking that approach.

48:48.280 --> 48:50.040
 Can you do something round up?

48:50.040 --> 48:52.080
 So some of those ideas seem like, OK,

48:52.080 --> 48:55.000
 that's the right direction in five years

48:55.000 --> 48:58.360
 we expect to see more in that area.

48:58.360 --> 49:01.760
 Other things we don't know is, will hardware accelerators

49:01.760 --> 49:03.200
 be the same?

49:03.200 --> 49:09.000
 Will we be able to train with four bits instead of 32 bits?

49:09.000 --> 49:11.440
 And I think the TPU side of things is exploring.

49:11.440 --> 49:13.960
 I mean, TPU is already on version three.

49:13.960 --> 49:17.520
 It seems that the evolution of TPU and TensorFlow

49:17.520 --> 49:24.080
 are coevolving in terms of both their learning

49:24.080 --> 49:25.720
 from each other and from the community

49:25.720 --> 49:29.720
 and from the applications where the biggest benefit is achieved.

49:29.720 --> 49:30.560
 That's right.

49:30.560 --> 49:33.320
 You've been trying with eager with Keras

49:33.320 --> 49:36.480
 to make TensorFlow as accessible and easy to use as possible.

49:36.480 --> 49:39.040
 What do you think for beginners is the biggest thing

49:39.040 --> 49:40.000
 they struggle with?

49:40.000 --> 49:42.080
 Have you encountered that?

49:42.080 --> 49:44.280
 Or is basically what Keras is solving

49:44.280 --> 49:48.680
 is that eager, like we talked about TensorFlow?

49:48.680 --> 49:51.480
 For some of them, like you said, the beginners

49:51.480 --> 49:54.840
 want to just be able to take some image model.

49:54.840 --> 49:58.040
 They don't care if it's inception or rest net or something else

49:58.040 --> 50:00.760
 and do some training or transfer learning

50:00.760 --> 50:02.440
 on their kind of model.

50:02.440 --> 50:04.400
 Being able to make that easy is important.

50:04.400 --> 50:08.560
 So in some ways, if you do that by providing them

50:08.560 --> 50:11.360
 simple models with, say, in Hub or so on,

50:11.360 --> 50:13.680
 they don't care about what's inside that box,

50:13.680 --> 50:15.120
 but they want to be able to use it.

50:15.120 --> 50:17.600
 So we're pushing on, I think, different levels.

50:17.600 --> 50:20.120
 If you look at just a component that you get, which

50:20.120 --> 50:22.800
 has the layers already smushed in,

50:22.800 --> 50:25.200
 the beginners probably just want that.

50:25.200 --> 50:27.360
 Then the next step is, OK, look at building

50:27.360 --> 50:29.000
 layers with Keras.

50:29.000 --> 50:30.600
 If you go out to research, then they

50:30.600 --> 50:33.120
 are probably writing custom layers themselves

50:33.120 --> 50:34.360
 or doing their own loops.

50:34.360 --> 50:36.320
 So there's a whole spectrum there.

50:36.320 --> 50:38.600
 And then providing the preentrain models

50:38.600 --> 50:44.760
 seems to really decrease the time from you trying to start.

50:44.760 --> 50:46.800
 So you could basically, in a Colab notebook,

50:46.800 --> 50:49.080
 achieve what you need.

50:49.080 --> 50:51.280
 So I'm basically answering my own question,

50:51.280 --> 50:54.240
 because I think what TensorFlow delivered on recently

50:54.240 --> 50:57.000
 is trivial for beginners.

50:57.000 --> 51:00.760
 So I was just wondering if there was other pain points

51:00.760 --> 51:02.480
 you're trying to ease, but I'm not sure there would.

51:02.480 --> 51:04.240
 No, those are probably the big ones.

51:04.240 --> 51:07.080
 I mean, I see high schoolers doing a whole bunch of things

51:07.080 --> 51:08.840
 now, which is pretty amazing.

51:08.840 --> 51:11.360
 It's both amazing and terrifying.

51:11.360 --> 51:12.640
 Yes.

51:12.640 --> 51:16.920
 In a sense that when they grow up,

51:16.920 --> 51:19.280
 some incredible ideas will be coming from them.

51:19.280 --> 51:21.800
 So there's certainly a technical aspect to your work,

51:21.800 --> 51:24.600
 but you also have a management aspect

51:24.600 --> 51:28.000
 to your role with TensorFlow, leading the project,

51:28.000 --> 51:31.080
 a large number of developers and people.

51:31.080 --> 51:34.680
 So what do you look for in a good team?

51:34.680 --> 51:37.400
 What do you think Google has been at the forefront

51:37.400 --> 51:40.440
 of exploring what it takes to build a good team?

51:40.440 --> 51:45.520
 And TensorFlow is one of the most cutting edge technologies

51:45.520 --> 51:46.120
 in the world.

51:46.120 --> 51:48.080
 So in this context, what do you think

51:48.080 --> 51:50.480
 makes for a good team?

51:50.480 --> 51:53.200
 It's definitely something I think a fair bit about.

51:53.200 --> 51:59.560
 I think in terms of the team being

51:59.560 --> 52:02.120
 able to deliver something well, one of the things that's

52:02.120 --> 52:05.800
 important is a cohesion across the team.

52:05.800 --> 52:10.400
 So being able to execute together and doing things,

52:10.400 --> 52:11.440
 it's not an end.

52:11.440 --> 52:14.120
 Like at this scale, an individual engineer

52:14.120 --> 52:15.400
 can only do so much.

52:15.400 --> 52:18.200
 There's a lot more that they can do together,

52:18.200 --> 52:21.640
 even though we have some amazing superstars across Google

52:21.640 --> 52:22.600
 and in the team.

52:22.600 --> 52:26.200
 But there's often the way I see it

52:26.200 --> 52:28.360
 is the product of what the team generates

52:28.360 --> 52:34.440
 is way larger than the whole individual put together.

52:34.440 --> 52:37.320
 And so how do we have all of them work together,

52:37.320 --> 52:40.000
 the culture of the team itself?

52:40.000 --> 52:43.000
 Hiring good people is important.

52:43.000 --> 52:45.600
 But part of that is it's not just that, OK,

52:45.600 --> 52:48.120
 we hire a bunch of smart people and throw them together

52:48.120 --> 52:49.720
 and let them do things.

52:49.720 --> 52:52.920
 It's also people have to care about what they're building.

52:52.920 --> 52:57.320
 People have to be motivated for the right kind of things.

52:57.320 --> 53:01.400
 That's often an important factor.

53:01.400 --> 53:04.600
 And finally, how do you put that together

53:04.600 --> 53:08.840
 with a somewhat unified vision of where we want to go?

53:08.840 --> 53:11.200
 So are we all looking in the same direction

53:11.200 --> 53:13.520
 or just going all over?

53:13.520 --> 53:16.040
 And sometimes it's a mix.

53:16.040 --> 53:21.400
 Google's a very bottom up organization in some sense.

53:21.400 --> 53:24.680
 Also research even more so.

53:24.680 --> 53:26.320
 And that's how we started.

53:26.320 --> 53:30.840
 But as we've become this larger product and ecosystem,

53:30.840 --> 53:35.040
 I think it's also important to combine that well with a mix

53:35.040 --> 53:37.920
 of, OK, here's the direction we want to go in.

53:37.920 --> 53:39.880
 There is exploration we'll do around that.

53:39.880 --> 53:43.320
 But let's keep staying in that direction, not just

53:43.320 --> 53:44.360
 all over the place.

53:44.360 --> 53:46.880
 And is there a way you monitor the health of the team?

53:46.880 --> 53:51.920
 Sort of like, is there a way you know you did a good job?

53:51.920 --> 53:53.000
 The team is good.

53:53.000 --> 53:56.960
 I mean, you're saying nice things, but it's sometimes

53:56.960 --> 54:01.120
 difficult to determine how aligned.

54:01.120 --> 54:04.480
 Because it's not binary, it's not like there's tensions

54:04.480 --> 54:06.680
 and complexities and so on.

54:06.680 --> 54:09.400
 And the other element of this is the mesh of superstars.

54:09.400 --> 54:12.880
 There's so much, even at Google, such a large percentage

54:12.880 --> 54:16.000
 of work is done by individual superstars too.

54:16.000 --> 54:19.920
 So there's a, and sometimes those superstars

54:19.920 --> 54:25.120
 could be against the dynamic of a team and those tensions.

54:25.120 --> 54:27.320
 I mean, I'm sure TensorFlow might be a little bit easier

54:27.320 --> 54:31.720
 because the mission of the project is so beautiful.

54:31.720 --> 54:34.760
 You're at the cutting edge, so it's exciting.

54:34.760 --> 54:36.640
 But have you had struggle with that?

54:36.640 --> 54:38.360
 Has there been challenges?

54:38.360 --> 54:39.800
 There are always people challenges

54:39.800 --> 54:41.240
 in different kinds of ways.

54:41.240 --> 54:44.520
 That said, I think we've been what's

54:44.520 --> 54:49.320
 good about getting people who care and have

54:49.320 --> 54:51.440
 the same kind of culture, and that's Google in general

54:51.440 --> 54:53.480
 to a large extent.

54:53.480 --> 54:56.760
 But also, like you said, given that the project has had

54:56.760 --> 54:59.160
 so many exciting things to do, there's

54:59.160 --> 55:02.080
 been room for lots of people to do different kinds of things

55:02.080 --> 55:06.440
 and grow, which does make the problem a bit easier, I guess.

55:06.440 --> 55:09.920
 And it allows people, depending on what they're doing,

55:09.920 --> 55:13.120
 if there's room around them, then that's fine.

55:13.120 --> 55:19.160
 But yes, we do care about whether a superstar or not

55:19.160 --> 55:22.560
 that they need to work well with the team across Google.

55:22.560 --> 55:23.760
 That's interesting to hear.

55:23.760 --> 55:27.960
 So it's like superstar or not, the productivity broadly

55:27.960 --> 55:30.520
 is about the team.

55:30.520 --> 55:31.520
 Yeah.

55:31.520 --> 55:32.960
 I mean, they might add a lot of value,

55:32.960 --> 55:35.720
 but if they're hurting the team, then that's a problem.

55:35.720 --> 55:38.720
 So in hiring engineers, it's so interesting, right?

55:38.720 --> 55:41.840
 The high rank process, what do you look for?

55:41.840 --> 55:44.240
 How do you determine a good developer

55:44.240 --> 55:47.280
 or a good member of a team from just a few minutes

55:47.280 --> 55:50.320
 or hours together?

55:50.320 --> 55:51.920
 Again, no magic answers, I'm sure.

55:51.920 --> 55:52.760
 Yeah.

55:52.760 --> 55:56.240
 And Google has a hiring process that we've refined

55:56.240 --> 56:00.880
 over the last 20 years, I guess, and that you've probably

56:00.880 --> 56:02.200
 heard and seen a lot about.

56:02.200 --> 56:05.280
 So we do work with the same hiring process in that.

56:05.280 --> 56:08.280
 That's really helped.

56:08.280 --> 56:10.880
 For me in particular, I would say,

56:10.880 --> 56:14.200
 in addition to the core technical skills,

56:14.200 --> 56:17.560
 what does matter is their motivation

56:17.560 --> 56:19.560
 in what they want to do.

56:19.560 --> 56:22.960
 Because if that doesn't align well with where we want to go,

56:22.960 --> 56:25.320
 that's not going to lead to long term success

56:25.320 --> 56:27.640
 for either them or the team.

56:27.640 --> 56:30.640
 And I think that becomes more important the more senior

56:30.640 --> 56:33.520
 the person is, but it's important at every level.

56:33.520 --> 56:34.920
 Like even the junior most engineer,

56:34.920 --> 56:37.680
 if they're not motivated to do well at what they're trying to do,

56:37.680 --> 56:39.080
 however smart they are, it's going

56:39.080 --> 56:40.320
 to be hard for them to succeed.

56:40.320 --> 56:44.520
 Does the Google hiring process touch on that passion?

56:44.520 --> 56:46.440
 So like trying to determine.

56:46.440 --> 56:48.440
 Because I think as far as I understand,

56:48.440 --> 56:52.000
 maybe you can speak to it that the Google hiring process sort

56:52.000 --> 56:56.360
 of helps the initial like determines the skill set there,

56:56.360 --> 56:59.840
 is your puzzle solving ability, problem solving ability good.

56:59.840 --> 57:05.000
 But I'm not sure, but it seems that the determining

57:05.000 --> 57:07.560
 whether the person is like fire inside them

57:07.560 --> 57:09.840
 that burns to do anything really doesn't really matter.

57:09.840 --> 57:11.520
 It's just some cool stuff.

57:11.520 --> 57:15.320
 I'm going to do it that I don't know.

57:15.320 --> 57:17.000
 Is that something that ultimately ends up

57:17.000 --> 57:18.840
 when they have a conversation with you

57:18.840 --> 57:22.600
 or once it gets closer to the team?

57:22.600 --> 57:25.400
 So one of the things we do have as part of the process

57:25.400 --> 57:28.600
 is just a culture fit, like part of the interview process

57:28.600 --> 57:31.040
 itself, in addition to just the technical skills.

57:31.040 --> 57:34.240
 And each engineer or whoever the interviewer is,

57:34.240 --> 57:38.800
 is supposed to rate the person on the culture and the culture

57:38.800 --> 57:39.960
 fit with Google and so on.

57:39.960 --> 57:42.160
 So that is definitely part of the process.

57:42.160 --> 57:45.800
 Now, there are various kinds of projects

57:45.800 --> 57:46.960
 and different kinds of things.

57:46.960 --> 57:50.040
 So there might be variants in the kind of culture

57:50.040 --> 57:51.320
 you want there and so on.

57:51.320 --> 57:52.720
 And yes, that does vary.

57:52.720 --> 57:54.920
 So for example, TensorFlow has always

57:54.920 --> 57:56.920
 been a fast moving project.

57:56.920 --> 58:00.920
 And we want people who are comfortable with that.

58:00.920 --> 58:02.640
 But at the same time now, for example,

58:02.640 --> 58:05.200
 we are at a place where we are also very full fledged product.

58:05.200 --> 58:08.440
 And we want to make sure things that work really, really

58:08.440 --> 58:09.320
 work right.

58:09.320 --> 58:11.680
 You can't cut corners all the time.

58:11.680 --> 58:14.320
 So balancing that out and finding the people

58:14.320 --> 58:17.560
 who are the right fit for those is important.

58:17.560 --> 58:19.720
 And I think those kind of things do vary a bit

58:19.720 --> 58:23.200
 across projects and teams and product areas across Google.

58:23.200 --> 58:25.240
 And so you'll see some differences there

58:25.240 --> 58:27.640
 in the final checklist.

58:27.640 --> 58:29.600
 But a lot of the core culture, it

58:29.600 --> 58:32.200
 comes along with just the engineering, excellence,

58:32.200 --> 58:34.720
 and so on.

58:34.720 --> 58:39.680
 What is the hardest part of your job?

58:39.680 --> 58:41.920
 I'll take your pick, I guess.

58:41.920 --> 58:44.440
 It's fun, I would say.

58:44.440 --> 58:45.520
 Hard, yes.

58:45.520 --> 58:47.240
 I mean, lots of things at different times.

58:47.240 --> 58:49.160
 I think that does vary.

58:49.160 --> 58:52.640
 So let me clarify that difficult things are fun

58:52.640 --> 58:55.720
 when you solve them, right?

58:55.720 --> 58:57.480
 It's fun in that sense.

58:57.480 --> 59:02.600
 I think the key to a successful thing across the board,

59:02.600 --> 59:05.320
 and in this case, it's a large ecosystem now,

59:05.320 --> 59:09.800
 but even a small product, is striking that fine balance

59:09.800 --> 59:12.000
 across different aspects of it.

59:12.000 --> 59:17.000
 Sometimes it's how fast you go versus how perfect it is.

59:17.000 --> 59:21.400
 Sometimes it's how do you involve this huge community?

59:21.400 --> 59:22.360
 Who do you involve?

59:22.360 --> 59:25.440
 Or do you decide, OK, now is not a good time to involve them

59:25.440 --> 59:30.160
 because it's not the right fit?

59:30.160 --> 59:33.640
 Sometimes it's saying no to certain kinds of things.

59:33.640 --> 59:36.880
 Those are often the hard decisions.

59:36.880 --> 59:41.000
 Some of them you make quickly because you don't have the time.

59:41.000 --> 59:43.200
 Some of them you get time to think about them,

59:43.200 --> 59:44.480
 but they're always hard.

59:44.480 --> 59:49.200
 So both choices are pretty good, those decisions.

59:49.200 --> 59:50.360
 What about deadlines?

59:50.360 --> 59:58.200
 Is this defined TensorFlow to be driven by deadlines

59:58.200 --> 1:00:00.360
 to a degree that a product might?

1:00:00.360 --> 1:00:04.920
 Or is there still a balance to where it's less deadline?

1:00:04.920 --> 1:00:08.920
 You had the Dev Summit, they came together incredibly.

1:00:08.920 --> 1:00:11.440
 Looked like there's a lot of moving pieces and so on.

1:00:11.440 --> 1:00:15.080
 So did that deadline make people rise to the occasion,

1:00:15.080 --> 1:00:18.360
 releasing TensorFlow 2.0 Alpha?

1:00:18.360 --> 1:00:20.360
 I'm sure that was done last minute as well.

1:00:20.360 --> 1:00:25.600
 I mean, up to the last point.

1:00:25.600 --> 1:00:28.600
 Again, it's one of those things that you

1:00:28.600 --> 1:00:29.960
 need to strike the good balance.

1:00:29.960 --> 1:00:32.040
 There's some value that deadlines bring

1:00:32.040 --> 1:00:33.920
 that does bring a sense of urgency

1:00:33.920 --> 1:00:35.720
 to get the right things together.

1:00:35.720 --> 1:00:38.280
 Instead of getting the perfect thing out,

1:00:38.280 --> 1:00:41.280
 you need something that's good and works well.

1:00:41.280 --> 1:00:43.720
 And the team definitely did a great job in putting that

1:00:43.720 --> 1:00:46.560
 together, so it was very amazed and excited by everything,

1:00:46.560 --> 1:00:48.680
 how that came together.

1:00:48.680 --> 1:00:50.640
 That said, across the year, we try not

1:00:50.640 --> 1:00:52.520
 to put out official deadlines.

1:00:52.520 --> 1:00:56.960
 We focus on key things that are important,

1:00:56.960 --> 1:01:00.600
 figure out how much of it's important,

1:01:00.600 --> 1:01:05.760
 and we are developing in the open, internally and externally,

1:01:05.760 --> 1:01:07.920
 everything's available to everybody.

1:01:07.920 --> 1:01:11.120
 So you can pick and look at where things are.

1:01:11.120 --> 1:01:13.160
 We do releases at a regular cadence,

1:01:13.160 --> 1:01:16.320
 so fine if something doesn't necessarily end up with this

1:01:16.320 --> 1:01:19.600
 month, it'll end up in the next release in a month or two.

1:01:19.600 --> 1:01:22.840
 And that's OK, but we want to keep moving

1:01:22.840 --> 1:01:26.520
 as fast as we can in these different areas.

1:01:26.520 --> 1:01:30.080
 Because we can iterate and improve on things, sometimes

1:01:30.080 --> 1:01:32.920
 it's OK to put things out that aren't fully ready.

1:01:32.920 --> 1:01:35.640
 If you make sure it's clear that, OK, this is experimental,

1:01:35.640 --> 1:01:37.960
 but it's out there if you want to try and give feedback.

1:01:37.960 --> 1:01:39.400
 That's very, very useful.

1:01:39.400 --> 1:01:43.560
 I think that quick cycle and quick iteration is important.

1:01:43.560 --> 1:01:47.200
 That's what we often focus on rather than here's

1:01:47.200 --> 1:01:49.200
 a deadline where you get everything else.

1:01:49.200 --> 1:01:52.880
 It's 2.0, is there pressure to make that stable?

1:01:52.880 --> 1:01:57.760
 Or like, for example, WordPress 5.0 just came out,

1:01:57.760 --> 1:02:01.760
 and there was no pressure to, it was a lot of build updates

1:02:01.760 --> 1:02:04.960
 that delivered way too late.

1:02:04.960 --> 1:02:06.440
 And they said, OK, well, we're going

1:02:06.440 --> 1:02:09.680
 to release a lot of updates really quickly to improve it.

1:02:09.680 --> 1:02:12.240
 Do you see TensorFlow 2.0 in that same kind of way,

1:02:12.240 --> 1:02:15.240
 or is there this pressure to once it hits 2.0,

1:02:15.240 --> 1:02:16.760
 once you get to the release candidate,

1:02:16.760 --> 1:02:19.440
 and then you get to the final, that's

1:02:19.440 --> 1:02:22.480
 going to be the stable thing?

1:02:22.480 --> 1:02:26.680
 So it's going to be stable in just like 1.0X

1:02:26.680 --> 1:02:32.080
 was where every API that's there is going to remain in work.

1:02:32.080 --> 1:02:34.800
 It doesn't mean we can't change things under the covers.

1:02:34.800 --> 1:02:36.720
 It doesn't mean we can't add things.

1:02:36.720 --> 1:02:39.200
 So there's still a lot more for us to do,

1:02:39.200 --> 1:02:41.080
 and we continue to have more releases.

1:02:41.080 --> 1:02:42.920
 So in that sense, there's still, I

1:02:42.920 --> 1:02:44.680
 don't think we'd be done in like two months

1:02:44.680 --> 1:02:46.160
 when we release this.

1:02:46.160 --> 1:02:49.880
 I don't know if you can say, but is there, you know,

1:02:49.880 --> 1:02:53.680
 there's not external deadlines for TensorFlow 2.0,

1:02:53.680 --> 1:02:58.520
 but is there internal deadlines, artificial or otherwise,

1:02:58.520 --> 1:03:00.840
 that you're trying to set for yourself,

1:03:00.840 --> 1:03:03.080
 or is it whenever it's ready?

1:03:03.080 --> 1:03:05.680
 So we want it to be a great product, right?

1:03:05.680 --> 1:03:09.880
 And that's a big, important piece for us.

1:03:09.880 --> 1:03:11.160
 TensorFlow is already out there.

1:03:11.160 --> 1:03:13.720
 We have 41 million downloads for 1.x,

1:03:13.720 --> 1:03:15.880
 so it's not like we have to have this.

1:03:15.880 --> 1:03:17.280
 Yeah, exactly.

1:03:17.280 --> 1:03:19.320
 So it's not like a lot of the features

1:03:19.320 --> 1:03:22.080
 that we've really polishing and putting them together

1:03:22.080 --> 1:03:26.240
 are there, we don't have to rush that just because.

1:03:26.240 --> 1:03:28.040
 So in that sense, we want to get it right

1:03:28.040 --> 1:03:29.920
 and really focus on that.

1:03:29.920 --> 1:03:31.520
 That said, we have said that we are

1:03:31.520 --> 1:03:33.520
 looking to get this out in the next few months,

1:03:33.520 --> 1:03:37.120
 in the next quarter, and as far as possible,

1:03:37.120 --> 1:03:40.000
 we'll definitely try to make that happen.

1:03:40.000 --> 1:03:44.360
 Yeah, my favorite line was, spring is a relative concept.

1:03:44.360 --> 1:03:45.960
 I love it.

1:03:45.960 --> 1:03:47.680
 Spoken like a true developer.

1:03:47.680 --> 1:03:50.200
 So something I'm really interested in,

1:03:50.200 --> 1:03:53.840
 and your previous line of work is, before TensorFlow,

1:03:53.840 --> 1:03:57.720
 you let a team and Google on search ads.

1:03:57.720 --> 1:04:02.840
 I think this is a very interesting topic on every level,

1:04:02.840 --> 1:04:07.200
 on a technical level, because if their best ads connect people

1:04:07.200 --> 1:04:10.080
 to the things they want and need,

1:04:10.080 --> 1:04:12.280
 and that they're worse, they're just these things

1:04:12.280 --> 1:04:15.840
 that annoy the heck out of you to the point of ruining

1:04:15.840 --> 1:04:20.240
 the entire user experience of whatever you're actually doing.

1:04:20.240 --> 1:04:23.600
 So they have a bad rep, I guess.

1:04:23.600 --> 1:04:28.080
 And on the other end, so that this connecting users

1:04:28.080 --> 1:04:32.120
 to the thing they need to want is a beautiful opportunity

1:04:32.120 --> 1:04:35.360
 for machine learning to shine, like huge amounts of data

1:04:35.360 --> 1:04:36.720
 that's personalized, and you've got

1:04:36.720 --> 1:04:40.400
 to map to the thing they actually won't get annoyed.

1:04:40.400 --> 1:04:43.760
 So what have you learned from this Google that's

1:04:43.760 --> 1:04:45.160
 leading the world in this aspect?

1:04:45.160 --> 1:04:47.560
 What have you learned from that experience?

1:04:47.560 --> 1:04:51.520
 And what do you think is the future of ads?

1:04:51.520 --> 1:04:54.040
 Take you back to the end of that.

1:04:54.040 --> 1:04:59.720
 Yes, it's been a while, but I totally agree with what you said.

1:04:59.720 --> 1:05:03.200
 I think the search ads, the way it was always looked at,

1:05:03.200 --> 1:05:05.520
 and I believe it still is, is it's

1:05:05.520 --> 1:05:08.240
 an extension of what search is trying to do.

1:05:08.240 --> 1:05:10.560
 The goal is to make the information

1:05:10.560 --> 1:05:14.680
 and make the world's information accessible.

1:05:14.680 --> 1:05:17.120
 With ads, it's not just information,

1:05:17.120 --> 1:05:19.120
 but it may be products or other things

1:05:19.120 --> 1:05:20.800
 that people care about.

1:05:20.800 --> 1:05:23.360
 And so it's really important for them

1:05:23.360 --> 1:05:26.480
 to align with what the users need.

1:05:26.480 --> 1:05:30.920
 And in search ads, there's a minimum quality level

1:05:30.920 --> 1:05:32.320
 before that ad would be shown.

1:05:32.320 --> 1:05:34.200
 If we don't have an ad that hits that quality bar,

1:05:34.200 --> 1:05:35.960
 it will not be shown, even if we have it.

1:05:35.960 --> 1:05:38.080
 And OK, maybe we lose some money there.

1:05:38.080 --> 1:05:39.560
 That's fine.

1:05:39.560 --> 1:05:41.200
 That is really, really important,

1:05:41.200 --> 1:05:43.000
 and I think that that is something I really

1:05:43.000 --> 1:05:45.040
 liked about being there.

1:05:45.040 --> 1:05:48.120
 Advertising is a key part.

1:05:48.120 --> 1:05:51.680
 I mean, as a model, it's been around for ages, right?

1:05:51.680 --> 1:05:52.920
 It's not a new model.

1:05:52.920 --> 1:05:57.440
 It's been adapted to the web and became a core part of search

1:05:57.440 --> 1:06:02.120
 and in many other search engines across the world.

1:06:02.120 --> 1:06:05.920
 I do hope, like I said, there are aspects of ads

1:06:05.920 --> 1:06:06.680
 that are annoying.

1:06:06.680 --> 1:06:09.600
 And I go to a website, and if it just

1:06:09.600 --> 1:06:12.160
 keeps popping an ad in my face, not to let me read,

1:06:12.160 --> 1:06:13.800
 that's going to be annoying clearly.

1:06:13.800 --> 1:06:22.080
 So I hope we can strike that balance between showing a good

1:06:22.080 --> 1:06:25.040
 ad where it's valuable to the user

1:06:25.040 --> 1:06:30.960
 and provides the monetization to the service.

1:06:30.960 --> 1:06:32.000
 And this might be search.

1:06:32.000 --> 1:06:33.680
 This might be a website.

1:06:33.680 --> 1:06:37.320
 All of these, they do need the monetization for them

1:06:37.320 --> 1:06:39.640
 to provide that service.

1:06:39.640 --> 1:06:45.720
 But if it's done in a good balance between showing

1:06:45.720 --> 1:06:48.040
 just some random stuff that's distracting

1:06:48.040 --> 1:06:50.920
 versus showing something that's actually valuable.

1:06:50.920 --> 1:06:55.360
 So do you see it moving forward as to continue

1:06:55.360 --> 1:07:00.960
 being a model that funds businesses like Google?

1:07:00.960 --> 1:07:05.160
 That's a significant revenue stream.

1:07:05.160 --> 1:07:08.080
 Because that's one of the most exciting things,

1:07:08.080 --> 1:07:09.680
 but also limiting things on the internet

1:07:09.680 --> 1:07:12.200
 is nobody wants to pay for anything.

1:07:12.200 --> 1:07:15.360
 And advertisements, again, coupled at their best

1:07:15.360 --> 1:07:17.360
 are actually really useful and not annoying.

1:07:17.360 --> 1:07:22.320
 Do you see that continuing and growing and improving?

1:07:22.320 --> 1:07:26.680
 Or is there GC sort of more Netflix type models

1:07:26.680 --> 1:07:28.960
 where you have to start to pay for content?

1:07:28.960 --> 1:07:31.000
 I think it's a mix.

1:07:31.000 --> 1:07:32.840
 I think it's going to take a long while for everything

1:07:32.840 --> 1:07:35.320
 to be paid on the internet, if at all.

1:07:35.320 --> 1:07:36.160
 Probably not.

1:07:36.160 --> 1:07:37.400
 I mean, I think there's always going

1:07:37.400 --> 1:07:40.760
 to be things that are sort of monetized with things like ads.

1:07:40.760 --> 1:07:42.800
 But over the last few years, I would say

1:07:42.800 --> 1:07:44.760
 we've definitely seen that transition

1:07:44.760 --> 1:07:48.560
 towards more paid services across the web

1:07:48.560 --> 1:07:50.360
 and people are willing to pay for them

1:07:50.360 --> 1:07:51.760
 because they do see the value.

1:07:51.760 --> 1:07:53.600
 I mean, Netflix is a great example.

1:07:53.600 --> 1:07:56.520
 I mean, we have YouTube doing things.

1:07:56.520 --> 1:07:59.720
 People pay for the apps they buy, more people

1:07:59.720 --> 1:08:03.120
 they find are willing to pay for newspaper content,

1:08:03.120 --> 1:08:07.240
 for the good news websites across the web.

1:08:07.240 --> 1:08:11.040
 That wasn't the case even a few years ago, I would say.

1:08:11.040 --> 1:08:13.280
 And I just see that change in myself as well

1:08:13.280 --> 1:08:14.840
 and just lots of people around me.

1:08:14.840 --> 1:08:19.240
 So definitely hopeful that we'll transition to that mix model

1:08:19.240 --> 1:08:23.400
 where maybe you get to try something out for free,

1:08:23.400 --> 1:08:24.120
 maybe with ads.

1:08:24.120 --> 1:08:27.080
 But then there is a more clear revenue model

1:08:27.080 --> 1:08:30.600
 that sort of helps go beyond that.

1:08:30.600 --> 1:08:34.760
 So speaking of revenue, how is it

1:08:34.760 --> 1:08:39.400
 that a person can use the TPU in a Google Colab for free?

1:08:39.400 --> 1:08:43.920
 So what's the, I guess, the question is,

1:08:43.920 --> 1:08:48.880
 what's the future of TensorFlow in terms of empowering,

1:08:48.880 --> 1:08:51.880
 say, a class of 300 students?

1:08:51.880 --> 1:08:55.920
 And I'm asked by MIT, what is going

1:08:55.920 --> 1:08:58.640
 to be the future of them being able to do their homework

1:08:58.640 --> 1:09:00.200
 in TensorFlow?

1:09:00.200 --> 1:09:02.800
 Where are they going to train these networks, right?

1:09:02.800 --> 1:09:07.720
 What's that future look like with TPUs, with cloud services,

1:09:07.720 --> 1:09:08.920
 and so on?

1:09:08.920 --> 1:09:10.240
 I think a number of things there.

1:09:10.240 --> 1:09:12.600
 I mean, any TensorFlow open source,

1:09:12.600 --> 1:09:13.640
 you can run it wherever.

1:09:13.640 --> 1:09:15.880
 You can run it on your desktop, and your desktops

1:09:15.880 --> 1:09:19.480
 always keep getting more powerful, so maybe you can do more.

1:09:19.480 --> 1:09:22.040
 My phone is like, I don't know how many times more powerful

1:09:22.040 --> 1:09:23.520
 than my first desktop.

1:09:23.520 --> 1:09:25.200
 You'll probably train it on your phone, though.

1:09:25.200 --> 1:09:26.200
 Yeah, that's true.

1:09:26.200 --> 1:09:28.080
 Right, so in that sense, the power

1:09:28.080 --> 1:09:31.440
 you have in your hand is a lot more.

1:09:31.440 --> 1:09:34.400
 Clouds are actually very interesting from, say,

1:09:34.400 --> 1:09:37.840
 students or courses perspective, because they

1:09:37.840 --> 1:09:40.040
 make it very easy to get started.

1:09:40.040 --> 1:09:42.040
 I mean, Colab, the great thing about it

1:09:42.040 --> 1:09:45.120
 is go to a website, and it just works.

1:09:45.120 --> 1:09:47.560
 No installation needed, nothing to, you know,

1:09:47.560 --> 1:09:49.960
 you're just there, and things are working.

1:09:49.960 --> 1:09:52.280
 That's really the power of cloud, as well.

1:09:52.280 --> 1:09:55.320
 And so I do expect that to grow.

1:09:55.320 --> 1:09:57.920
 Again, Colab is a free service.

1:09:57.920 --> 1:10:00.840
 It's great to get started, to play with things,

1:10:00.840 --> 1:10:03.080
 to explore things.

1:10:03.080 --> 1:10:08.200
 That said, with free, you can only get so much, maybe.

1:10:08.200 --> 1:10:11.080
 So just like we were talking about free versus paid,

1:10:11.080 --> 1:10:15.280
 and there are services you can pay for and get a lot more.

1:10:15.280 --> 1:10:16.000
 Great.

1:10:16.000 --> 1:10:18.480
 So if I'm a complete beginner interested in machine

1:10:18.480 --> 1:10:21.560
 learning and TensorFlow, what should I do?

1:10:21.560 --> 1:10:24.240
 Probably start with going to a website and playing there.

1:10:24.240 --> 1:10:26.560
 Just go to TensorFlow.org and start clicking on things.

1:10:26.560 --> 1:10:28.440
 Yep, check out tutorials and guides.

1:10:28.440 --> 1:10:30.680
 There's stuff you can just click there and go to Colab

1:10:30.680 --> 1:10:31.320
 and do things.

1:10:31.320 --> 1:10:32.360
 No installation needed.

1:10:32.360 --> 1:10:34.040
 You can get started right there.

1:10:34.040 --> 1:10:34.840
 OK, awesome.

1:10:34.840 --> 1:10:36.720
 Roger, thank you so much for talking today.

1:10:36.720 --> 1:10:37.440
 Thank you, Lex.

1:10:37.440 --> 1:10:46.680
 Have fun this week.