What's a good way to learn network security?

You could go to your local bookstore and buy a book. I’ve probably walked by hundreds of network security books at Barnes & Noble.

do you have an antivirus system?
and a cleaner?

@FrogOnFire any recommendations?

@cyndihugs well obviously. But I’m looking for ways to code more securely.

Take the CompTIA Security + certification test. It costs money and you have to study real hard for it, but it’s worth it. I know a lot more about computer security.

http://www.comptia.org/certifications/listed/security.aspx

If you’re looking for a way to test the security of your coding, and you know your way around a command line, you can try BackTrack.