In this article, it talks about how to create a safe, reliable password and the dangers of not having one. Some of the ways to have a safe password are avoiding using the same password twice - if someone gets into an account with a password, they're going to try to get into other accounts of yours with the same password. You shouldn't use easily identifiable names, and you should change your passwords regularly. I really agree with the stress to use different passwords. I once had my facebook hacked, and because they got my email from that and I was using the same password for AOL mail as I was for facebook, they got into my email and nearly into my paypal. It's always a good idea to change your passwords often and keep them long and well thought out.
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