I cannot imagine living without file revisioning, like #git
Having used them daily for the previous 30 years, I don't understand how developers work without #branches, #merging, #diffs.
#visualsourcesafe #cvs #svn #hg #git it doesn't matter - it's the concept of revisioning and being and to "go back in time".
#Revisioning also for binaries, Word documents and Excels, of course. What else?