Protect Yourself (and me)
We are at a point on the internet where you need at least three protections on your computer. You can get reasonable protection in all three areas for free.
1. Virus protection -- I use AVG.
2. Firewall -- This keeps people from directly accessing your computer. If you are on the internet and don't have a firewall, your computer can be accessed by anyone who knows how. I use Zonealarm.
3. Spyware remover -- As you browse the web, spyware can somehow get attached to your browser. It sends information about your browsing habits to whoever has placed the spyware on your computer. I run ad-adware every so often and usually find some spyware.
It is a good idea to check for updates on all three of these softwares. It appears they should automatically update, but I find that they don't, and I usually find something whenever I run them manually, every month or so.