For today there exist several thousands of types of malicious software (malware) that function differently and have strict classification. All malware are united by the fact that they are created specially for destruction, blocking, modification or copying of the information without user’s authorization, for computer or computer network disorder.


Computer viruses

Computer virus is spread within one computer. Unlike worms, viruses don’t use network services for spreading and penetration to other computers. A copy of the virus gets into remote computers only in case if an infected object for an independent of virus functionality reason appears to be activated on other computer.

Network worms

Standard viruses and worms, that users know the most, have the ability of self-replication in computers and computer networks unauthorized by users. Don’t confuse them with trojans horse software not on any account. The main feature, by which virus and worms behavior is distinguished, is the way of their spreading. Almost all network worms are spreading in the form of a file with an *exe extension. However, there exist viruses that “live” in the form of network packets.

Trojan horses

Trojan horses are created for performing of functions unauthorized by user, that are aimed to elimination, blocking, modification or copying of information, also to computer work disfunction. At that trojans can’t create their copies. Trojan horse software types are distinguished by their unauthorized actions. Trojans give a remote access to another’s computer. At that, initially malicious functions are not built in the program, but a malicious code owner can steal confidential information of a victim, possess victim’s passwords and so on.

Malicious utilities

Apart from above described programs there exist so-called “malicious utilities” that are developed for automatic performance of creation of other viruses, for organization of DoS-attacks and hackings of other computers.

How to protect yourself

The most efficient way to get rid of the virus – is to avoid the infection. For this purpose it won’t be enough only to install an antivirus. It is necessary to regularly check for its updating and to download last virus definitions. Apart from that it is necessary to be attentive when working in the internet: don’t follow unknown links and don’t download suspicious files.