Revision Control is a very powerful feature and is easy to use. The concept of revision control is so that if a mistake has been made when updating or editing a page, that page can be brought back to an earlier version.

At the bottom of the page when editing content, there is a Publishing Options link which drops down a menu. Leave the 'Published' box checked, and make sure the 'Create new revision' is checked as well. This creates a new copy of the page and uses it.

If you see the reason to need to return a page to a previous version, click the 'Revisions' link above the Title bar. From here you can view and compare old revisions to the most current one, and change accordingly.