Version: best example is QTP 9.0 9.2 9.5 and current one 10 version another example is Microsoft 98 2000 NT XP Vista Whenever some changes are added to the existing functionality of application a new pattern will be generated and the new application is termed as new version.
(Compare the window OS or QTP with their version and changes added to them in release after release)
Build generally in development life cycle you wont develop all the modules with in a month and release the project instead development will be done module after module for the sake the management will decide when will be the build dates some companies take 1 month to 3 months to release first build and it depends on project duration so Module 1 will be developed and release it to testing team to test the application and on second release module 2 will developed after and integrate it with Module 1(along fixing the issues found in release one) that how the all the modules will be developed and release to test team till all the modules are developed.
so first release is termed as Build 1 and second release will be termed as Build 2 and so on.
Correct me if i am wrong