COMPUTER VIRUSES

VIRUS                                                                                                                                                     Is the type of malware that when execute replacing by inserting copies of it self into other files.These programs can have many effects ranging from wiping a hard drive and displaying a joke in a small box, or doing nothing at all except to replicate itself.                                                                                                TYPES OF VIRUSES
The many different types computer virus as explained below                                                                                                                                                                  1.POLYMORPHIC VIRUS                                                                                                                      Polymorphic virus is a complicated computer  virus that affect data types and function also they  have ability to mutate implying that they change the viral code known as the signature each time they spread or infect. Thus an antivirus program which is scanning for specific virus codes unable to detect it's presence.           2.BOOT SECTOR VIRUS                                                                                                                 Boot sector virus is a virus that place its own codes and command into a computer DOS boot sector and it . infect either the master boot record of the hard disk or the floppy drive. The boot record program responsible for the booting of operating system is replaced by the virus. The virus either copies the master boot program to another part of the hard disk or overwrites it. They infect a computer when it boots up or when it accesses the infected floppy disk in the floppy drive                                                                                                                                                      3.STEALTHY VIRUS                                                                                                                              Is the virus that make use of special method to hide it self from being detected by user or virus scanner so its . stealthy in nature. They sometimes remove themselves from the memory temporarily to avoid detection by antivirus software and other time its difficult to detect. When an antivirus program tries to detect the virus, the stealth virus feeds the antivirus program a clean image of the file or boot sector.                                         4.FILE/PROGRAM VIRUS                                                                                                                     Is the types of malware that infects executable with the intent to course permanent damage or make them unusable.This virus types it may infect various number of system include window and UNIX                                                                   .                                                                                          5.MULTIPARTITE VIRUSES                                     .                                                                           A multipartite virus is a computer virus that infects and spread in multiple ways , and remains recursively infective in each target. It attempts to attack both the boot sector and the executable, or programs, files at the same time. When the virus attaches to the boot sector, it will in turn affect the system’s files, and when the virus attaches to the files, it will in turn infect the boot sector.
                                                                                                                                                 6.MARCO VIRUSES                                                                                                                             A macro virus is a computer virus that "infects" a Microsoft Word or similar application and causes a sequence of actions to be performed automatically when the application is started or something else triggers it. Macro viruses tend to be surprising but relatively harmless.A macro virus is often spread as an e-mail virus. Well-known examples are Concept Virus and Melissa Worm.
If you use a computer, read the newspaper, or watch the news, you will know about computer viruses or other malware. These are those malicious programs that once they infect your machine will start causinghavoc on your computer. What many people do not know is that there are many different types of infections that are categorized in the general category of Malware.
MALWARE                                                                                                                                              Is the malicious software in which is used to disrupt a computer operation,gather sensitive information or gain access to private computer system Thus, malware includes computer viruses, worms, Trojan horses, spyware, hijackers, and certain type of adware.
This article will focus on those malware that are considered viruses, trojans, worms, and viruses, though this information can be used to remove the other types of malware as well. We will not go into specific details about any one particular infection, but rather provide a broad overview of how these infections canbe removed. For the most part these instructions should allow you to remove a good deal of infections, but there are some that need special steps to be removed and these won't be covered under this tutorial.
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BACKDOOR                                                                                                                                          A backdoor means access to a computer program that bypasses a security mechanism, These types of programs are typically used to launch attacks on other computers, distribute copyrighted software or media, or hack other computers.
HIJACKER                                                                                                                                             A program that attempts to hijack certain Internet functions like redirecting your start page to the hijacker's own start page, redirecting search queries to a undesired search engine, or replace search results from popular search engines with their own information.
SPYWARE                                                                                                                                               A program that monitors your activity or information on your computer and sends that information a remote computer without your Knowledge.
AD WARE                                                                                                                                                A program that generates popups on your computer or displays advertisements. ­ It is important to note that not all adware programs are necessarily considered malware.
There are many legitimate programs that are given for free that display ads in their programs in order to generate revenue. As long as this information is provided up front then they are generally not considered malware.
DIALER                                                                                                                                                  A program that typically dials a premium rate number that has per minute charges over and above the typical call charge. These calls are with the intent of gaining access to pornographic material.
TROJAN                                                                                                                                                 A program that has been designed to appear innocent but has been intentionally designed to cause some malicious activity or to provide a backdoor to your system.
WORM                                                                                                                                                   A program that when run, has the ability to spread to other computers on its own using either mass-mailing techniques to email addresses found on your computer obey using the Internet to infect a remote computer using known security holes.