Periodically backing up your computer is always a good idea. You want to make sure your documents, photos, and files are protected in case of hardware failure, software glitches, or malware attacks.

This morning, the hard drive in my trusty 2007 iMac died. So, I went and picked up a nice cheap replacement (1 TB Hitachi, I think), and slapped it in thanks to the wonderful guys at iFixit. It booted ...