Help, I was sitting in front my computer and it started acting strange! Pop-ups were on my screen and I was not even surfing the web. My home page was changed somehow and so did other web settings. My programs are at a crawl and overall my computer is just not working the way it should be.

If this sounds like your computer, chances are you have been infected with some type of malicious software. Several types of software can infect your computer; some of these are spyware, a virus, a Trojan, and a worm. That is why you need security software.

Below is a brief and simple description of the software that can infect your computer and cause poor performance.