<new_branch>::
Name for the new branch.
+<tree-ish>::
+ Tree to checkout from (when paths are given). If not specified,
+ the index will be used.
+
<branch>::
- Branch to checkout; may be any object ID that resolves to a
- commit. Defaults to HEAD.
+ Branch to checkout (when no paths are given); may be any object
+ ID that resolves to a commit. Defaults to HEAD.
+
When this parameter names a non-branch (but still a valid commit object),
your HEAD becomes 'detached'.
++
+As a special case, the "`@\{-N\}`" syntax for the N-th last branch
+checks out the branch (instead of detaching). You may also specify
+"`-`" which is synonymous with "`@\{-1\}`".
Detached HEAD
------------
+
<1> switch branch
-<2> take out a file out of other commit
-<3> restore hello.c from HEAD of current branch
+<2> take a file out of another commit
+<3> restore hello.c from the index
+
If you have an unfortunate branch that is named `hello.c`, this
step would be confused as an instruction to switch to that branch.