Yet another revision control system

Git is new to me. Git is probably the 5th or 6th revision control system that I have used (i.e. sccs, rcs, ...).

Setting up git merge and git diff using opendiff
http://stackoverflow.com/questions/21486481/is-it-possible-to-view-git-diffs-using-a-gui-side-by-side-tool-on-mac