Types of computer viruses that can impact your PC

Today many types of computer viruses exist and it has cause a great many people and companies serious issues. The software has grown as technology has grow and today combating these infections and removing PC viruses is now big business. These Malware programs can lead to system crashes as well as system slow downs or even the deleting of system files. The first question to answer is 'knowing the enemy' that creates these programs.

THE ENEMY - Crackers and Hackers

Geeks make a distinction between crackers, who break into systems to do damage, and hackers who enjoy taking programs apart just to see how they tick. We'll stick with the more common, though less accurate, term of hacker. (The term 'hacker' originally meant 'someone who makes furniture' with an axe. Crude, but effective - like most computer viruses.)

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Types of computer viruses are actually a particular type of computer 'malware' - a general term covering all types of malicious software. The most common types are viruses, worms and Trojan horses.


A Computer virus or malicious code is usually hidden inside another program such as an installation program delivered via e-mail attachment. (Biological viruses require a host organism to live and reproduce, hence the name.) When the 'host' program is run, the virus program also runs. Once it's in memory the virus is able to do its dirty work, which usually includes infecting other programs.

After the infection stage of these types of computer viruses, there's a destructive stage. The virus waits for a pre-determined trigger (such as a specific date or a certain number of times the virus has replicated itself) before delivering its 'payload'. Payloads range from simple messages to file deletion commands to destruction of the core operating system.

When first developed, computer viruses were commonly distributed on floppy disks or CD's. However with the growth of the Internet downloaded files and e-mail are the preferred delivery mechanisms. E-mail can contain attachments which can be any kind of computer file. Any executable file can be infected with a virus, and shouldn't be run unless you're confident they're virus free.


Worms are similar to viruses and malicious code in that they're self-replicating. These types of computer viruses reproduce themselves across networks without human assistance, such as e-mail sending. A worm, though, doesn't need another executable program to be distributed.

Worms usually affect networks more than individual computers on the network. Their self-replicating behavior can overload network resources, causing slowdowns in data transmission by consuming massive bandwidth normally used to forward normal traffic. Network systems that route Internet traffic are just specialized computer hardware and software. They, too, can be affected by malware.

Worms can also be designed to carry a payload, using a 'backdoor' installation program. A backdoor is a hidden access point to a computer that bypasses the normal login procedure. They're commonly used by spammers to distribute junk e-mail, for example.


Trojan horses are the third common type of malicious code. A 'Trojan' is a program that pretends to do one thing but actually does something different. (The term comes from the story of the Greeks who built a large wooden horse in which to hide. Their enemies, the Trojans persuaded they'd receive a gift, took the horse inside their compound giving the Greeks easy access to wreak havoc.) Unlike viruses or worms, a Trojan doesn't replicate itself.

Trojans may be hidden in otherwise useful software. Once started they can do almost anything including erasing data, corrupting files, installing backdoors and logging keystrokes so that hackers can steal information such as credit card numbers and passwords.


Normally know as ad-ware this type of software is most often spread via the Internet or over network connections. At one time spyware was just used to monitor a person activity in terms of product searches however now it is use for much more. This is the newest types of computer viruses you can get on your computer. Ad-ware can infect your computer system with programs that Hijack your browser or even transmit a virus program that over writes existing files. It is easy to get these file even going to the wrong site can infect your system.

How to Fight Malware and Spyware

So how do we fight these types of computer viruses? The best solutions are Anti-Virus along with a good Spyware protection. It also helps to have installed Firewall software such as Zone alarms. You have to be proactive and not to be passive and expect the problem to be solved by other. Fighting viruses requires active participation from vendors, webmasters as well end users.

Is your computer infected? Or is your computer running slow? If so then be sure to check your computer system and fix the problem today. If you need the right software for your computer than be sure to check the offers from the vendors on this web page.

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