What is computer virus?
Virus or worm is a computer program that can be spread on the computer or network in a way to make copies of itself without the computer owner. The virus can cause a very harmful effect, for example, from displaying the message, steal data or even control your computer from distance.
How virus to infected your computer?
The first time a virus must be run before he was able to infect your computer. There are various ways that this virus can be executed by the victim, such as with glue him on a program the other. There is also the virus that way when you open a particular file type. Often the virus also take advantage of the rift in the security of your computer (the operating system or application), by using these things, the virus can run and will then spread itself automatically.
You can also receive a file that is infected with a virus attachment in your e-mail. Once you run the file, the virus code will run and start infected your computer and can also spread to all the files on your computer network.
Trojan horse is a program that seems like a valid program or normal, but the actual program code with carrying functions that are very dangerous for your computer.
For example, the virus D Loader-L come from the e-mail attachment and is considered as an update program from Microsoft for Windows XP operating system. If you run this file then it will download the program and will utilize your computer to connect your computer to a particular website. The target, of course, to make a website before overload and ultimately can not be accessed properly by the other party. This is often called a denial of service attack or (DoS).
Trojan can not spread as fast as a virus, trojan because it does not make a copy of itself automatically. But in line with the development of the virus, the trojan horse can work together with the virus to propagate itself in the case. The virus is able to download a trojan to store data on your keyboard keystroke or steal the information on your computer. On the other hand, trojan also be used for a computer with a virus.
Worm can be similar to the virus but the worm does not require a carrier in this program or a document. Worm is able to make copies of it and use the network communication between computers to spread itself. Many viruses such as My Doom or Bagle worm work as the withdrawal and use e-mail to do forward itself to other parties.
Often disrupt the virus or you stop working on your computer when needed. In line with the development of the computer virus in the world at this time until the effects of this virus is more and more.
The virus can spread through e-mail, such as the Sobig virus, and to be able to create e-mail traffic which is very large, of course, will make the server become slow or even a crash. Even if it does not happen until the company who felt disturbed by incidents such as this server will be decided.
Steal personal data
Bugbear-D Worm, for example, able to store personal data about your keyboard keystroke, including passwords and so forth. Earlier recordings will usually be sent to the creator of the virus to be used more.
Use your computer to attack a site
MyDoom, for example, it infected many computers around the world to attack the SCO site traffic data is very large. This will make the site will extraordinary and will eventually crash and can not serve other users. This is called the common denial of service (DoS).
Leaving the others to hijack your computer
Some put the trojan virus backdoor on the computer and this will make the creator of the virus can be connected to the computer and can be used further in accordance with the desires.
Virus compatible, for example, can make changes to the data you store on the MS Excel document.
Sircam virus, for example, attempt to remove or to overwrite your hard drive at a certain time the unexpected.
Displays a message
Cone-F virus, for example, will display a message if an element of political month of May shows. Damage your credibility. If the virus get forward itself from your computer to the computer of your customers or business partners your computer, then this will damage your reputation as an organization and they will no longer want to continue a business relationship with you or may claim compensation from your part.
Create your shame
PolyPost virus, for example, will make the document and post your name on the newsgroups that contain pornography.