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From the Revisions tab, you can view the individual revisions, revert to an earlier revision, and delete revisions.
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Another useful feature of the revision system is the Revision log message field, which appears near the Create a new revision check box on the content editing form. If you add a message to the Revision log message field when saving a revision, that message will appear on the Revisions tab along with the revision. It is a good idea to add a meaningful Revision log message whenever you create a content revision, so others can see what you changed and why, without having to actually view the previous revision.
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