Computer Security 101 Free online course

Computer security can be a difficult concept for many people. There are so many strange words and acronyms that it can seem like someone is talking a foreign language when they are discussing it.
The Free Computer Security 101 Class begins by explaining what some of those terms and acronyms mean. If you understand what they mean and how they're used with your computer and the Internet, then you can also understand the problems they cause and what you need to do to protect yourself.

This Class will also cover many of the attacks and vulnerabilities to watch out for and the common defense mechanisms like antivirus software and firewalls.

It is a 10-day class followed by a Final Exam. I just started this course. The 10 days start when you sign up start and is given by http://netsecurity.about.com
You will receive the first lesson as soon as you sign up, and the other nine lessons and the Final Exam around 8am ET the next ten days.
You cannot change your email address in the middle of the class, so be sure to use an address you'll have access to for at least 10 days.

Again, here is the link for 'the class'