Ways of deleting a remote branch:
$ git push origin --delete <branch> # Git version 1.7.0 or newer
$ git push origin :<branch> # Git versions older than 1.7.0
Ways of deleting a local branch:
$ git branch --delete <branch>
$ git branch -d <branch> # Shorter version
$ git branch -D <branch> # Force delete un-merged branches
Ways of deleting a local remote-tracking branch:
$ git branch --delete --remotes <remote>/<branch>
$ git branch -dr <remote>/<branch> # Shorter
Ways of deleting multiple obsolete tracking branches
$ git fetch <remote> --prune
Shorter version of the same:
$ git fetch <remote> -p