Warning updating the currently checked out branch may cause confusion dating a vintage gibson
However, when no confusion will result, we often just use the term "branch" both for branches and for branch heads.
even if the branch points to a commit not reachable from the current branch, you may know that that commit is still reachable from some other branch or tag.
In that case it is safe to use this command to force git to delete the branch.
$ git checkout v2.6.17 Note: moving to "v2.6.17" which isn't a local branch If you want to create a new branch from this checkout, you may do so (now or later) by using -b with the checkout command again.
In the following, we say that commit X is "reachable" from commit Y if commit X is an ancestor of commit Y.