This just some basic knowledge with some links below:

Computer viruses are designed to spread from one computer to another quickly. Here's what Webopedia says about computer viruses:

"A program or piece of code that is loaded onto your computer without your knowledge and runs against your wishes. Viruses can also replicate themselves. All computer viruses are manmade. A simple virus that can make a copy of itself over and over again is relatively easy to produce. Even such a simple virus is dangerous because it will quickly use all available memory and bring the system to a halt. An even more dangerous type of virus is one capable of transmitting itself across networks and bypassing security systems."

Some computer viruses don't do anything malicious -- others can wipe out everything on your hard drive.

Worms are self-propagating computer viruses. Webopedia defines a worm as:

"A program or algorithm that replicates itself over a computer network and usually performs malicious actions, such as using up the computer's resources and possibly shutting the system down." Their impact is similar to computer viruses.

Trojan Horses are closely related to computer viruses, but they differ in that they do not attempt to replicate themselves. More specifically, a Trojan Horse performs some undesired -- yet intended -- action while, or in addition to, pretending to do something else. A common example is a fake login program, which collects account information and passwords by asking for this info just like a normal login program does.

Here's what Webopedia says about Trojan horses, including where the term comes from:

"A destructive program that masquerades as a benign application. Unlike viruses, Trojan horses do not replicate themselves but they can be just as destructive. One of the most insidious types of Trojan horse is a program that claims to rid your computer of viruses but instead introduces viruses onto your computer.

"The term comes from a story in Homer's Iliad, in which the Greeks give a giant wooden horse to their foes, the Trojans, ostensibly as a peace offering. But after the Trojans drag the horse inside their city walls, Greek soldiers sneak out of the horse's hollow belly and open the city gates, allowing their compatriots to pour in and capture Troy."

Spywhere is software that tracks your actions and/or your Internet use. It can capture what you type on your keyword, including passwords, and send it to the spyware creator. Here's what Webopedia says about spyware:

"Any software that covertly gathers user information through the user's Internet connection without his or her knowledge, usually for advertising purposes. Spyware applications are typically bundled as a hidden component of freeware or shareware programs that can be downloaded from the Internet; however, it should be noted that the majority of shareware and freeware applications do not come with spyware. Once installed, the spyware monitors user activity on the Internet and transmits that information in the background to someone else. Spyware can also gather information about e-mail addresses and even passwords and credit card numbers.

"Spyware is similar to a Trojan horse in that users unwittingly install the product when they install something else.

"Aside from the questions of ethics and privacy, spyware steals from the user by using the computer's memory resources and also by eating bandwidth as it sends information back to the spyware's home base via the user's Internet connection. Because spyware is using memory and system resources, the applications running in the background can lead to system crashes or general system instability."

Adware is "a form of spyware that collects information about the user in order to display advertisements in the Web browser based on the information it collects from the user's browsing patterns."

Scumware changes how you view websites you visit. It replaces the actual content of sites with ads from scumware advertisers, and generates traffic for the scumware advertisers.

Note: Every single day we hear about viruses causing major PC crashes, PC's being hacked into, Spyware installed without their permission, and even private information stolen.

The inconvenience and cost of repairing this physical damage is considerable, but the psychological effect can be devastating.

Yet it's relatively simple to protect yourself! But if that's the case, why do millions of people never protect themselves as they should?

It's because installing security and safety precautions APPEARS to be costly, technical and intimidating. So the vast majority of people don't do it -- with devastating consequences!

We found a simple solution: It's called 'The 'PC & Internet Security Kit'.

For the first time, you can bullet proof your PC and personal information without any technical knowledge and without spending an arm and a leg doing it. This is not a free resource, but it's well worth it. Click here to read all about it.

Our other favorite resources on computer viruses and hoaxes:

Symantec's latest virus threats and security advisories
http://www.symantec.com

McAfee virus info and recent threats
http://us.mcafee.com/virusInfo/

List of the latest computer hoaxes
http://www.f-secure.com/hoaxes/hoax_new.shtml