How do computers store Information on there hard drives?

Is the data electricity? Would an EMP attack erase all informatioon on hard drives in its blast radius?

I know alot about computers but just always thought about that but never asked.

Thanks!

How do computers store Information on there hard drives?antivirus protection

Yes! Information is stored magnetically on the disks. I guess in retrospect it would depend on how close, and how strong the electromagneticpulse was to the computer. Just my 2cents!

How do computers store Information on there hard drives?computer repair

try this great site:

http://en.wikipedia.org/wiki/Harddrive