Revisions allow you to track differences between multiple versions of your content, and revert back to older versions.
Copy of the revision from Mon, 28/06/2010 - 15:48.
Copy of the revision from Fri, 25/06/2010 - 10:32.
Copy of the revision from Wed, 23/06/2010 - 12:01.
Copy of the revision from Tue, 01/06/2010 - 23:01.
Copy of the revision from Fri, 28/05/2010 - 21:38.