About Revisions
With the revision command you can create a new version of an object that can be sent along a different life cycle path. Revisions also denote the maturity of an object. You should revise an object whenever you need to update a design or whenever there is a major shift in a design's intent.
For example, object A is an assembly that represents a product that your company is currently manufacturing. Your company also plans to make an updated version of object A for release next year. Rather than modifying object A which is required by your manufacturing division, you can make a revision of object A called object B. You can then make all the necessary modifications to object B while object A remains intact. When you check in object B to the Windchill PDM server, other users are able to view both object A and object B. The later revision level of object B indicates to other users that object B is significantly different from object A.
For more information on revisions, refer to the Windchill Online Help.