So, I had a follow-up question regarding Anti-Virus software. 

How can my computer STILL get infected if I have anti-virus software?

What is Malware?  Malware is short for malicious software.  It is any software that is designed to infiltrate a computer without the users consent.  Malware includes the following attack vectors:

Computer Virus -A program that can copy itself and infect a computer.
Worm – A special type of virus that is self-replicating.
Trojan Horse – A destructive program that masquerades as a benign application.  (ring a bell? Greek History … Trojan Horse?) This program can collect and transmit data, gain remote access to your computer, or destroy different components of the computer – this is known as a Denial of Service  (DoS) attack.
Spyware – Any software that covertly gathers user information through the user's Internet connection without his or her knowledge, … Read More »