How to Browse & Revert to Prior Versions of a File in Mac OS X
All modern releases of Mac OS X include a powerful built-in version control system that allows a user to revert to any previously saved version of a file or document, assuming the app supports the version revision feature. This ability is often overlooked by Mac users, but it can be a real lifesaver when you’ve caught yourself having modified a file inadvertently, or discovered that recent changes to a document should be undone. In some sense, you can think of this feature like a file-level “Undo” feature included in OS X, and it works fairly similar to the Time Machine backup browser on the Mac.