fetches the submodule's remote repository before calculating the
SHA-1. If you don't want to fetch, you should use `submodule update
--remote --no-fetch`.
++
+Use this option to integrate changes from the upstream subproject with
+your submodule's current HEAD. Alternatively, you can run `git pull`
+from the submodule, which is equivalent except for the remote branch
+name: `update --remote` uses the default upstream repository and
+`submodule.<name>.branch`, while `git pull` uses the submodule's
+`branch.<name>.merge`. Prefer `submodule.<name>.branch` if you want
+to distribute the default upstream branch with the superproject and
+`branch.<name>.merge` if you want a more native feel while working in
+the submodule itself.
-N::
--no-fetch::