Check a File Out/In
The Check Out option is only available on files in a Collaborative Workspace.
A workspace member can Check Out a file to make changes, and can later check the file back in to make the changes available to the other workspace members. While a file is checked out, other workspace members can view the file, but may not edit. By making the file unavailable to workspace members while one member revises and makes changes, we eliminate the possibility of multiple members making changes to the same file at once.