Why You Need Protection It's a rough world out here in cyberspace. Those of us who thought the Internet would bring a new era of cooperation, where technology brings out the best in people have been rudely awakened. We see the same old thieves and vandals as in the real world. Luckily, there are ways to protect yourself. But to do so, you should first know your enemy. Here are some of the threats you should watch out for: Hackers try to take over other peoples computers, usually to steal your files, vandalize your hard drive, or use your computer as a base to launch other attacks. (Unfortunately, if these other attacks are noticed, it looks like you are doing the hacking!) Many hackers also create viruses, worms, and Trojan horses, below. Viruses and worms are nasty little programs that spread from computer to computer. Sometimes that's all they do, but sometimes they delete files, send mail from your computer, and open "back doors" for hackers to take control of your computer. Viruses and worms can arrive on a computer through email, or by exploiting flaws or holes in applications or your operating system. Trojan horses (or just "Trojans") are programs that secretly do bad things that you don't expect--like a screen saver that also secretly emails your bank statements to a hacker, or "spyware" that monitors your web-surfing habits and reports back to its creator. They can get onto your computer the same way as viruses and worms, or you might install one on purpose, never suspecting that the "harmless" screensaver your friend just sent you is actually dangerous.