Githug is designed to give you a practical way of learning git. It has a series of levels, each utilizing git commands to ensure a correct answer.

Guide to Xcode version control (Git)

1. Pull the update from master, or whereever – git pull
2. See the dreaded merge failed message
3. Edit the files which failed to merge correctly cleaning up the code
4. Run your tests / specs just to make sure you caught everything
5. Add and commit the manually merged file. git add path/to/file.rb; git commit -m “work damnit”
6. Go back to pushing and pulling in peace

Git - with missions! (last two #git links via @roguelynn)

git - the simple guide #git via @rogerdudler