Thoroughly Destroy the Data on an Old Hard Drive

The back of my home office has a stack of obsolete hard drives. Why? Because I always pull them out of my PCs before I sell, donate, or recycle them -- it prevents data theft. Eventually, though, you need to either get rid of your drives or build a backyard fort out of them for your kids. Thankfully, I've got three strategies for definitively making your old data unreadable.

Rub Out Your Most Sensitive Files and Folders. If you have a limited set of sensitive data, you can make do with destroying just those files, and then do a standard format to wipe everything else. This is a fast, easy, and convenient approach. I recommend a program like Freeraser, which can thoroughly erase documents just by dragging and dropping them into a Freeraser trash bin.

Erase the Entire Drive to Milspec Standards. Darik's Boot and Nuke (the cool kids call it DBAN) is a free program that can completely wipe the contents of your hard disk by overwriting each sector on the drive -- rendering it utterly unrecoverable without involving the FBI. If you don't mind creating the DBAN boot disk on CD or a USB memory key and waiting for the wipe, this is the best plan for giving away an old drive.

Smash It. Have a stack of old drives that you can't reformat because they use an obsolete interface? Or they're too small to donate or sell? No problem, recycle them. But before you do that, make sure no one can ever extract your old bank account numbers or e-mail passwords with the business end of a drill or hammer. You can drill completely through the hard drive in a few places, being sure to pierce the drive platters, or smash the casing with a hammer. Either way, protect your eyes from flying metal bits.

Photo by Robert Scoble