2. Computer viruses are programs written by people and they are programed specially to damage the data on our computer by corrupting programs, deleting files, or erasing our entire hard drive.

3. Malwares are malicious softwares designed to infiltrate a computer system without the owner´s informed consent. Malware is sometimes knowns as a computer contaminant and it includes computer viruses, worms, troyan horses, spyware…

5. The basic different types of computer viruses consist of troyan horses,worms and email viruses.

6. Troyan horses can do an incredible amount of damage to your PC. They attack when your computer security is concerned and it is imppossible to notice them, even when you are looking specially for them. They need a host program to be able to inffect.

7. A worm is one of the most common types of computer viruses, and these types of viruses work by using computer networks and security flaws to be able to create copies to itself. They don´t need a host program to be able to infect.

8. They use email messages to transport,and can automatically send itself to hundres and thousands of people depending whose email address they victimize

10. Some malwares and other viruses have symtoms noticeable to the computer user. When new viruses are discovered, anti-virus software is upted to deal with them on weeks or months.