sentence: contents list the standard is divided into the following chapters : foreword introduction annex a ( informative ) units in the cgs system with special names annex b ( informative ) units based on the foot , pound , second , and some other related units annex c ( informative ) other non-si units given for information , especially regarding the conversion factors names , symbols and definitions space and time space iso 80000-3 : 2006 assigns names and symbols to quantities and units of space and time , and defines these quantities and units .