Would you ever know it if your computer were taken over and being used by a hacker? Not likely. When a hacker hijacks a computer, the victim rarely knows. A computer that has been hijacked is one that is completely taken over by a hacker, or a group of hackers, to be used for their own purposes. The idea is that the real owner of the computer never knows their system has been hijacked, so the hacker(s) can secretly use it whenever and however they want.

Once a computer has been hijacked, the hacker claims ownership of that computer. In fact, in many cases when a hacker has taken over a computer, they will even "heal" the computer by closing the security holes, so no other hacker can break into the computer and use it too. Computers that have been hijacked and are under the control of a hacker are known as "zombies".

Some of the more popular uses for a Zombie computer include using it to send Spam emails, distribute pornography, download illegal copies of software, and to anonymously attack another computer, a business, a website, or even a government agency.

There have been many cases in the U.S. and around the world where a business or home computer has been hijacked and used for illegal purposes without the computer owner's knowledge. These victims have had their computers used to distribute child pornography, deface websites, and even hack into government computers. In many cases, the owner of the hijacked computer (the business owner or the homeowner) has been arrested and hauled off to jail, only to be humiliated, demoralized and even convicted for crimes they didn't commit. Hackers are very good at hiding behind their slave or zombie computers. A hijacked computer is a hacker's protection of anonymity.

As unbelievable as it may seem, hijacked computers or "zombie" computers actually have a street market valuein the hacker community. The better the computer and the faster the Internet connection of the slave machine, and the bigger the hard drive, the more it is worth on the market. Zombie computers are often leased out by hackers to other hackers, or even to organized crime groups, to be used for illegal purposes - without the computer owner's knowledge. If a hacker or a cyber-gang can take over a hundred or a thousand computers, they have an army of computers at their disposal.

FACTS:

. If your computer has become a "zombie" or a "slave" to a hacker, the use of your computer could be for sale somewhere on the Internet or an auction website. Your computer's power is valuable to hackers.

. Today, there are organizations that claim "ownership" of more than 450,000 zombie computers around the world that they use to anonymously send spam.