Ask the Blogger: Magnets and Computers

by Mary Ann Romans | More from this Blogger

18 Apr 2008 03:25 PM

I recently received the following question from a reader. "I want to dispose of my computer, but I am worried that someone might be able to find my personal information on the computer if I donate it or throw it out. I heard that sticking a magnet on the hard drive will erase any data. Is this true?"

Dear Reader,

While it is true that magnets can be used to erase a hard drive, just any old household magnet won't do the job. The only magnets that are powerful enough for such a task as usually found in laboratories or in government agencies. And even then, these magnets generally only erase a bit of data at a time, rather than the entire drive. In actuality, your hard drive already contains a magnet that helps swing the head of the disk.

The best way to ensure that your data is gone for good is to rewrite over it. Otherwise the data may appear gone, but it is not forgotten. When you erase something on your hard drive, you don't actually lose the data, just the connections to it. When new data occupies the space where old data once lived, then it is gone for good. Heidi Computers makes a downloadable program for the PC called Eraser.

The process is a little easier with a flash drive. Again, magnets won't help here, not even the ones in labs, since flash data is different. Try rewriting the space here by filling it with something unimportant, such as a photo of a brick wall, over and over again.

The one bit of computer storage that can be ruined by a household magnet is the old 3.5 inch floppy disk. Stick a magnet to the disk for a few seconds and your data is ruined forever.

Mary Ann Romans writes about everything related to saving money in the Frugal Blog, technology in the Computing Blog, and creating a home in the Home Blog. You can read more of her articles by clicking here.

Related Articles:

Identifying E-Mail Hoaxes

Learn more about Mary Ann Romans

Mary Ann Romans is a freelance writer, wife and mother of three children. She lives in Pennsylvania with her husband, the kids and a 16-pound cat.

View Full Profile | More from this Blogger