The answer is very simple. To protect your computer from damage and to prevent the computer is used to transmit infection to other computers without your knowledge.

Many people are reluctant to pay cash to provide antivirus software. I remember at about $ 50 for a decent antivirus program is not exactly small change. But look more closely at the costs for a moment:

PC -> $ 600 - $ 4,000
Monitor -> $ 250 - $ 1000
Software -> $ 500 - $ 5000
Internet connection -> $ 25 + / month
Personal data / Business -> Priceless

Therefore, at the lower end of the scale we are seeing a reversal of similar equipment in the price of a used older car at the top, like a new car used.

Maybe I'm wrong, but I guess you would not buy a used car that had removed all the locks and do not need a key to start it, and comes with a free "Steal Me" sign on it too.

Having a computer that is not up to date antivirus protection is absolutely the same. It is simply asking for trouble.

And the problems you find.

How I can be so sure? Simply because that is what viruses, worms, malware, etc. can be done. Your only job is to find unprotected computers and attack and kidnapping of them without their knowledge. These things are very good at what they are built to do, and never stop. If your computer is not protected, and share disks or go online, it becomes infected.

The best antivirus software programs cost as little as 2 months internet connection. They all include constant and unlimited automatic updates that keep the system clean and safe.

If you can afford $ 1500 + on a computer, $ 300 + / year in Internet connections, you can definitely pay another $ 50 once it is safe (and prevent it being used to spread viruses and Trojan horses behind your back) .

Anything else would be uncivilized!

PS Some people have begun to make claims that if you do not use antivirus software should be held legally responsible if your machine is used as part of an attack (although you did not know).