Computer viruses can easily spread from one computer to another by attaching itself to programs and files. Do you know what greatly contributes to the spread of virus into you computer and to other computers? It is the action done by the user.

Viruses come in executable files. Meaning, it will not really affect your computer unless you run or open the malicious program. Oftentimes, because the user is not aware of malicious files and programs, they initiate it and this causes the activation within the computer.

There are a lot of anti-virus programs you can choose from which will enable you to protect your computer. Yet, it is still important to be aware about viruses because this will ensure that you can really avoid those malicious programs and files.

It is not enough to just know what a virus is. More importantly, you have to be aware of the other common threats that usually affect computers. Among the most common viruses are worms and Trojan horse. What exactly are these?

Worm is an algorithm which can cause damage your computer. The difference of worm among other computer threats is that is capable of spreading through your computer even without running or opening the program. It spreads from one computer to another through various methods of file transfer. What makes it worse is the fact that worms are often capable of replicating itself within your system.

On the other hand, Trojan horse is also another destructive program which can be quite tricky. Worms are capable of appearing in disguise. People who receive Trojan horse are often fooled into opening the file because it appears like a useful software or a program file from a reliable source. Trojan horse can do alterations to your computer like changing the desktop settings or adding unnecessary icons. In other cases, it causes more serious damage like deleting files in the hard drive.

If you think these two are already serious threats to your computer, there's something else that is much worse. That is, if virus, worm and Trojan horse were put together in one seriously destructive threat which is also called as the Blended Threat. Blended threats are more sophisticated and more complicated to create. At the same time, it also has a more detrimental effect. It can spread through the entire computer and even to networks which damages the files and programs and can even sacrifice the safety of confidential information within the system. Even worse, blended threats do not need to be activated by the user before it could attack your system, destroying the computer, the network and programs.

Keep yourself aware of these things and it will strengthen your defense against the viruses that may destroy your computer.