Computer Virus are some illegal or mischievous programs that when run, they are able to copying itself by infecting different many files and programs on your computer system. There are many types of harmful computer virus like Email viruses, Worms, and Trojan horses and many more.
Definition of a Computer Virus
These are mischievous computer programs which is developed by the programmer. These programs are copying itself without your knowledge and these are very harmful for your computer system. A computer virus is an executable program. These virus are directly destroy contents of your hard disk, and they also disturb regular task of your computer. It is a mischievous program, when you run this program, it has the capacity to self-multiply by infecting different files and programs on your computer system. It treat like a joke in which capture your entire hard disk by self-replicating. There are some few examples of computer virus are: Trojans, worms, and viruses. Email viruses are able to extent very speedily than other viruses, because they are sent via email. E.g. Melissa virus comes in March, 1999. ILOVEYOU virus, comes in May 4, 2000.
Signs of a computer virus
If your computer is infected by the virus attack then you check these given signs in your computer:
- Your computer performance will be very slow.
- Behavior of your computer will be changed.
- Accidently your date will be lost.
- Repeatedly your computer will be crashed.
Modes of Viruses:
1) Boot Sector Virus: – This kind of virus directly crash your main booting record from the hard disk or floppy disk. Without booting you are not able to run the operating system in your computer. This virus remove or create another copy of the main booting program to any other part of your hard disk. As soon as your start your pc it directly enter into your boot section and infected all programs. There are few examples of boot area viruses are “Stoned” & “Michelangelo”.
2) Files or Program Viruses: – When you open files or execute any programs, this virus loads in to the computer memory and corrupt your system settings. This virus effect of given below some important file extensions like .EXE (Executable), .COM (Command), .BIN (Binary), .DRV (Device Driver) and .SYS (System).Eg. “Cascade” and “Sunday”.
3) Multi-platform Viruses: – This kind of virus effect on multiple platforms. It directly attack on the boot sector include the executable file and programs at the real time. It effect the computer system file.Eg. Invader, Flip and Ghostball. Ghostball.
4) Stealth Viruses: – These kind of virus are very difficult for detect. They covering themselves to escape deduction during the scanning process. 5) Macro Viruses: – These kind of virus are effected on macros, which is created in MS-Word or other related application programs. Normally these kind of virus are harmless. It is spread via sending or receiving an e-mail. Eg. “Melissa-Worm” & “Concept” Virus.
Malware – Malware is developed by the programmer in a programming language due to harm your computer system. Malware includes following computer viruses like worms, Trojan horses, spyware, hijackers. Backdoor- With admin permission, backdoor permits a remote user to run the on your computer. These programs are designed to attack on computers.
Hijackers– This kind of program is mainly used to hijack some internet task like forwarding your starting page to the starting page of hijacker’s.
Spyware- It is program which is used to observers all completed activities on your computer and sends all these report to the remote computer without your permission.
Trojan horse-These programs are working in your computer in backside. These are simple computer programs and they comes in your computer system during downloading any games via internet. It normally remove important contents from your hard disk. It is different from a simple virus, because it doesn’t attempt to reproduce itself. These kind of virus are discovered quickly by your antivirus program.
Worm- This type of program is a small codes which is used to break your computer network and security holes. Worm normally attack on Windows 2000 and NT 4.0. It is used to search some unsecured servers and copied itself to them and break network security.