Time Machine lets you automatically back up your entire system in Mac OS X v10.5 or later. It keeps an up-to-date copy of everything on your Mac  – digital photos, music, movies, TV shows, documents, and so forth. If you ever have the need, you can easily go „back in time“ to recover files.

Learn more:

1. http://www.apple.com (What is TimeMachine?)
2. http://support.apple.com (How to setup, how to search back in time, how to restore a file)
3. http://docs.info.apple.com (How to search and restore a file)
4. http://www.dummies.com (TimeMachine for Dummies)
5. http://reviews.cnet.com (How to restore a specific file)
6. http://www.soma-zone.com (Extended, more powerful search interface for Time Machine)
7. http://www.macworld.com (How to monitor what Time Machine is doing)
8. http://support.apple.com (A list of TimeMachine tricks and Work-a-rounds)