Anti-virus is pretty much a necessity to EVERYONE that has a computer. If you use the computer 24/7 or just to check email every once in a while you NEED some sort of Anti-virus protection/scanning. If you do not want to purchase this software you have a variety of choices available free for download.
Panda Anti-VirusQuickly becoming the biggest source of problems on the internet Spyware is EVERYWHERE these days. From popup windows to redirecting you to different websites Spyware is pretty much unavoidable. There are two options to avoid this. Purchase a program for a couple of hundred $'s that will actively protect your computer for it or download a free program that will remove it once it gets on there. Me, I'm a big fan of the free option. On my computer I have 3 different Anti-Spyware programs on there. The last one listed, the Microsoft one, I have not personally tried but have heard quite a few good things about.
Lavasoft Ad-AwareWhat does a firewall do? A firewall basically hides your computer from the internet. Ideally what it does is makes it so that you can see the internet but the internet cant see you. This means that no hackers can get into your computer. Here are some examples of good firewall programs that are worth a shot.
Zone AlarmTrojans are a different breed of virus. Like the name suggests just like the old trojan horse legend once these trojans are in your computer they typically will open a backdoor to allow a hacker to have remote access to your computer. Once they have this access they can do anything on your computer that you can. They can install new programs, try to send junk email/viruses using your computer, hack into the playboy.com website and give Glyn an eternal free account. Below are some really good ways of keeping your computer free of trojans.
Trojan HunterHere are some other links that have some useful information or downloads to help out with your computers
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