Computer virus may be defined as the computer programs written by programmers in diverse computer languages. Computer virus is capable of preventing computer from booting. The virus is a program coded by the programmers to create unfavorable effect on the operation of the computer. Computer virus can easily be spread from one computer to another through the use of affected diskette. For example, if Mr. Uwana Andy has a diskette with a computer virus and he goes to a business centre to run his programs with that diskette. The computer that he uses to run the program will automatically be infected with virus, but if on the other hand he has gone to the business centre with a clean "clean" diskette. i.e. non virus infested diskette and the system he used in running his program has a virus. His diskette will also be infected with virus. The chain may continue for a very long time. Just like AIDS is being transmitted from one person to another as a result of personal contact or blood transfusion. Virus is very harmful and dangerous to the computer as they are capable of rendering the computer useless by destroying the program of the diskette or the hard disk.
Examples of computer virus are as followers
- Stone
- Antiexe
- Data Luck
- Michael Angelo
- Angell
- November 17
- Jerusalem Doodle etc.
- Trojan horse
- Sleeper
- Logic Bomb
- Alabama Virus
- Christmas Virus, etc.
Characteristic of Computer Viruses
- Invisibility: Computer virus are invisible. They can only be detected by anti virus computer
- Fast Reproduction: Computer virus is capable of spreading very fast.
- Manifestation of several systems: Computer virus manifests its presence in different ways which include the showing down of the operation of a system.
- Transmission: Computer virus are caught by a system or program from a source and passed to another system or program.
Sources of Viruses
- Infected diskette
- Infected CD-ROMS
- Internet downloads
- Illegal duplication of software, etc.
Virus Warning signs
- Slowing down of response time
- Presence of tiny dots
- Wandering across the screen
- Incomplete saving of file
Computer (Virus Detection)
There are several computer anti viruses that can be used to reverse the adverse effect of computer viruses. These include.
- Disk tool
- Mac Afee Virus scan
- Central point anti virus (CPA)
- Norton disk doctor (NDD)
- Dr. Solomon anti virus tool kit
- Kaspersky Anti Virus
Prevention of Computer Virus
- The diskette must be well protected
- The write protect notch must be well covered with a write protection tab.
- A diskette should not be used carelessly
- User's Hygiene: every computer user must observe some computer hygiene rules when using program
- Backups: A clean backup of internal data should be kept. It is important to mention that backup is very useful for replacing infested files.
- System Inoculation: It is necessary to inoculate a system by installing an anti-virus program
- Shareware program: the used of shareware program among other should be done with caution.
- User Awareness: Every computer user should be aware of the existence of computer virus.
- Installation of anti virus software: These are programs protect system software, application software and data against viruses. They are loaded automatically into the computer's memory and storage devices to delete any viruses round. The two must popular anti-virus software packages are Norton Anti-virus and Mc Acfee Virus scan.
- Do not open an email attachment that contains are executable bile with the extensions EXE, COM OR VBS