This article Familiar with Types of computer viruses, performance antivirus and antivirus detection and cleaning of viruses that are introduced. The information also stated that it is necessary to choose the right tools and a number of anti-virus programs will be compared with each other.
If a computer infected with the virus are different depending on the type of disaster that may occur computer system that in some cases their compensation imposes large costs. Independent of the type of virus that must be dealt with, there is always a need for anti-virus programs and in the absence of various anti-virus products have been produced, select the right software is user concern.
Types of computer viruses:
Computer viruses are programs that are similar to biological viruses spread into the computer and then doing the unexpected actions. While all viruses are not dangerous, but most of them aimed at the destruction of certain types of files, applications or operating systems are written.
Viruses similar to all the other programs of system resources such as memory and hard disk space, CPU and other resources can benefit And can perform dangerous acts such as delete files or entire hard disk to format. A virus can also access the device through the network without authentication provided.
For the first time in 1984, the term “virus” in the sense used by Fred Cohen in academic texts. In this article, that “experiments with computer viruses” was the author of a particular category of programs called viruses and this name is attributed to Leonard Adleman. Before this time the virus in the body of practical and imaginative story had appeared.
Common types of viruses can be divided into the following categories:
boot sector on a floppy disk or computer hard drive is the first Sector. In this sector of executable code stored in the computer activities done using them. Given that every time you boot up Boot sector is referred to, and each time you change the configuration of the computer content re-written the boot sector, this sector is very vulnerable to virus attacks is the place.
This type of virus through infected floppy disk boot sector that have spread. infect. These viruses can act in such a way that as long as the infected machine is able to boot the computer from the hard disk to be wiped out.
These viruses then try to write on the original boot sector source code to other sectors on the disk and transferred it as a bad block (Bad Sector) mark.
These viruses do not infect programs directly. The purpose of this class of viruses files that are generated by programs such as documentation Exel or Word macro programming language they use. Macro viruses through the disk, or network attached file with e-mail is expandable.
It is possible to activate only when the virus infected file is opened, then the virus began to spread in the computer and other files are infected. Transfer the files to other computers or to share files between different devices spread of the infection.
File infecting viruses:
Executable files (files ending in .exe and .com) and coincides with the implementation of these programs to infect your device memory and time began to spread and infect other executable files to their system. Some examples of these viruses text to text rather than executable files are located.
Polymorphic viruses (Polymorphic):
The virus in any infected files as they appear. Since the encryption algorithms used are clean and their trail, detection and diagnosis of such a virus is difficult.
These viruses try to hide from the operating system and antivirus software. To do this in memory-resident virus and retaining access to the operating system. The question that all anti-virus software virus to the operating system receives. The anti-virus software also comes cheated and there is a perception that there is no virus in the computer. The virus also fooled User and memory usage secretly doing.
The most common types of boot sector viruses and file infecting viruses are combined. Incorporating a variety of other viruses is possible.
Other disturbing security programs:
Some researchers Trojan horse (Trojan), worms and logic bombs are not in the category of viruses, but the reality is that these programs are very dangerous and can seriously damage a computer system.
Trojans pretend they are doing something special, but in practice have been made for another purpose, For example, a program that pretends to be a game, but in fact they allow remote access to the computer provides a user.
Worms are similar to viruses can multiply your plans are, but unlike other programs that do not need them to spread to infect them and entitled infected files to the transfer and not contaminate the other devices. Worms usually vulnerable parts of the wide and immediate dissemination programs for e mail if required.
Logic bombs are programs at predetermined times, such a special day, doing unexpected things. These programs did not infect other files and do not spread your day. Despite the spread of viruses and Internet threats may be using anti-virus software largely coped with the virus and to the general risks of the Internet.