Bonus:
In speaking of pull & fetch in the above answers, I would like to share an interesting trick,
git pull --rebase
This above command is the most useful command in my git life which saved a lots of time.
Before pushing your new commits to server, try this command and it will automatically sync latest server changes (with a fetch + merge) and will place your commit at the top in git log. No need to worry about manual pull/merge.
Find details at: http://gitolite.com/git-pull--rebase
