Tip - How Do I Securely Wipe a Computer?

Dear Lifehacker, I have a few old computers I'm planning to donate to charity, but I want to make sure that all of my data is off of them before I give them away. I'd rather not pull out the hard drives since they're so old. How can I make sure they're clean before giving them away? Signed, Partially Paranoid You can reach Alan Henry, the author of this post, at , or better yet, follow him on or .
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