In this chapter, I explained why and how to back up your Mac. I began by covering the basic questions of what you should back up, how often, to what media, and in what form — and emphasized the importance of being able to easily restore backed-up files. I listed some of the most important criteria to consider when choosing backup software. For those who choose to use Time Machine, I provided a thorough description of how to back up and restore data with this utility built into Leopard and Snow Leopard.
I also explained how to make bootable duplicates of your Mac's startup disk, described the virtues and pitfalls of backing up your data over the Internet, and talked about managing your backup media (including offsite copies). Finally, I discussed the use of RAIDs to provide protection against drive failure and how this is different from a backup.