FREE ESSAY ON COMPUTER VIRUSES

COMPUTER VIRUSES

Anna L. Porter
Professor J. Brown
Information Systems 201
December 1, 1998
Computer Viruses
A computer virus is an illegal and potentially damaging computer program designed to
infect other software by attaching itself to any software it contacts. In many cases,
virus programs are designed to damage computer systems maliciously by destroying or
corrupting data. If the infected software is transferred to or accessed by another
computer system, the virus spreads to the other system. Viruses have become a serious
problem in recent years, and currently, thousands of known virus programs exist (Reed
85-102).
Three types of viruses are a boot sector viruses, file virus, and Trojan horse virus. A
boot sector virus infects the boot program used to start the system. When the infected
boot program executes, the virus is loaded into the computer's memory. Once a virus is in
memory, it can spread to any floppy disk inserted into the computer. A file virus inserts
virus code into program files. The virus then spreads to any program that accesses the
infected file. A Trojan horse virus (named after the Greek myth) hides within or is
designed to look like a legitimate program.
Some viruses interrupt processing by freezing a computer system temporarily and then
displaying sounds or messages. Other viruses contain time bombs or logic bombs. A time
bomb is a program that performs an activity on a particular date. A logic bomb is a
program that performs an activity when a certain action occurs, such as an employee being
terminated. A worm, which is similar to a virus, copies itself repeatedly until no memory
or disk space remains.
To detect computer viruses, antivirus programs have been developed. Besides the detecting
of the viruses, antivirus programs also have utilities to remove or repair infected
programs or files. Some damaged files cannot be repaired and must be replaced with
uninfected backup files. The table below outlines some techniques used to protect
computer systems.
Table
Techniques for Virus Protection and System Backup
Using Virus Protection Software Backing Up Your System
Install virus protection software on every computer system. Develop a regular plan for
copying and storing important data and program files.
Before use, scan every floppy disk with a virus scan program to check for viruses.
Implement a backup plan and adhere to its guidelines.
Check all programs downloaded from the Internet or bulletin boards for viruses. Keep
backup copies of files in fireproof safes or vaults or off-site
If your system becomes virus infected and you have questions, contact the National
Computer Security Association (NCSA) for low-cost assistance (Elmhurst, 6 Nov. 1998).
Works Cited
Chambers, Anita R., and Zachary W. Peters. "Protecting Against Virus Attacks." Computers
May 1998: 45-62.
Elmhurst, Mark. "Virus Infection: Where to Obtain Assistance" Word 97, Project 3.
http://www.scsite.com/wd97/pr3.htm (6 Nov. 1998).
Reed, Margaret E. An Introduction to Using Computers. Chicago: West Davidson Jones
Publishing Company , 1998.
Bibliography
Works Cited
Chambers, Anita R., and Zachary W. Peters. "Protecting Against Virus Attacks." Computers
May 1998: 45-62.
Elmhurst, Mark. "Virus Infection: Where to Obtain Assistance" Word 97, Project 3.
http://www.scsite.com/wd97/pr3.htm (6 Nov. 1998).
Reed, Margaret E. An Introduction to Using Computers. Chicago: West Davidson Jones
Publishing Company , 1998.