Up to now, there are still many people do not know what is a computer virus. Therefore, I write this article to let you have a better understanding of computer viruses.

What is a computer virus?
A computer virus is a computer program that can infect your computer system by executing itself without your permission or knowledge and run against your wishes. Viruses can also replicate itself to maximize the infection.

What is a computer program?
A computer program is a list of instruction for a computer to execute.

Basically, people create computer programs to do good things such as music player, video player, email programs, calculator and many more. They are all helpful program which bring benefits to the people.

Unfortunately, some people write programs to do bad things such as programs that might corrupt or delete your files or documents on your hard drive or programs that might send your private data(ex. credit card number) to strangers or to the writer himself. This kind of program is known as computer virus.

Why we call it a VIRUS?
Well, it’s just like a human virus, it can be very dangerous and destructive. It can also spread itself from one computer to another by many ways. For instance, viruses are most easily spread by attachments in e-mail messages or instant messaging messages over the network or the internet. Viruses are also easily spread by carrying it on a removable medium such as floppy disk, USB drive or CD.

What is the difference between viruses, worms and Trojan horses?
Some people distinguish between general viruses, worms and Trojan horses. A worm is a special type of malware programs that can replicate itself and use memory, but cannot attach itself to other programs, and a Trojan horse is a file that appears harmless until executed.

So, what should we do to protect our computer against viruses?
Click here to read how to avoid virus infections.