The Windows Registry is a database that holds your operating system's configurations and settings. This includes everything from how long your mouse must hover over a taskbar icon before the preview pops up (in Windows Vista and Windows 7) to performance settings.

Windows 7 (and Vista) have more eye-candy features built into the operating system, but a number of Registry hacks and tweaks can speed up--or, at least, appear to speed up--the performance of your computer. Before we start mucking around with your PC's guts, however, we're going to make sure that you have a reliable backup of your Registry in case something goes sour.