We’ve been talking a lot about updating to Mac OS X 10.7 (Lion) lately, as well as compatibility status with various music and audio software packages. (Check out our Lion Compatibility page for up-to-the-minute info.)
Given this, it seems a prudent time to re-iterate the Number One Rule for Computer OS Upgrades: back up first! Before you even think about installing a new operating system, make a complete back up of your system hard drive, and verify that your back up is good. Only then should you proceed with installing the new OS.
The Number One Rule for Computer OS Upgrades applies regardless of whether you are running Mac OS, Windows, or any other OS.