You're sick. You've got a fever, the chills, and a headache so horrible that you can't think straight. No matter who claims to desperately need your help, you are not going to get out of bed. Your computer can suffer the very same thing--a virus. And, in the worst-case scenario, it might cause your computer to refuse to start up.

The term "virus" in the computer world comes from exactly where you might think--the term used for illnesses like the common cold.

We've all heard of nasty worms that can infest our dogs and cats. They can seriously harm our pets if left untreated. Well, the same can be said for the worms that can crawl through your computer, too.

Computer worms are programs that reproduce themselves by using networks to send clones of themselves to other computers that are attached to the network-and they do so without any help from you.

At some point during school you probably learned about Odysseus's brilliant plan to sneak soldiers into his enemy's city in the guise of a magnificent statue of a horse-the famous Trojan horse, to be exact. It's a great story, and the plan was such a great tactical maneuver that, unfortunately, hackers have adapted it to suit their malicious attacks against your computer.

You might have a spy in your home, and it's not James Bond. Heck, it's not even human! Your computer might be collecting your personal information and passing it on to companies and people anywhere in the world. That's because there might be spyware on your computer without you even knowing it.

Spyware is software designed to collect information about you for a variety of purposes, including advertising, credit card fraud, and identity theft.

If you spend any time at all on the Internet, you can hardly avoid the copious ads that appear on nearly every site you visit. Advertising in and of itself isn't a bad thing. It makes people who do business over the Internet able to bring in some money and keep their venture going. There's nothing wrong with making a little money! Unfortunately, a type of software called "adware" has sprung up for advertising purposes, and it can seriously affect your computer.

More and more people are turning to the Internet as a means to make a living, or to add to their income from a regular nine-to-five job. In fact, recent estimates indicate more than 40 million Americans are looking to start a home-based business through the Internet.

The question then becomes, "How do I make a living online if I do not know what I am doing?" That is a pretty valid question.

The Internet has opened up a world of possibilities for individuals seeking to earn money through home businesses. Some people even derive their entire income from online businesses and avoid the need for outside employment of any kind. Others use their home business as a means of supplementing income from a regular job so that they can pay for things like home improvements and tropical vacations.