Very solid mini intro to Git by Tobias Gunther over at A List Apart. You can find this content virtually anywhere by running a simple Google search, but Tobias makes a stronger case. First he succinctly lays out the reasons why Git is such an improvement over older repository systems like Subversion. There’s also some great use of visuals here to lay out what happens during core commands like ‘git reset’ and ‘git revert’.