What is a computer virus?
(Lansing State Journal, May 17, 1995)
Any time an infected program runs, the virus program also runs, and a new copy is made.
For almost all viruses, this happens without letting there person using the computer know.
There are many different viruses that produce different results. Some will alter the output seen on the computer screen, while others will quietly accumulate in other programs until they no longer function. Some viruses can actually destroy all of the date on a hard drive.
There are several things that can be done to help protect your computer from computer viruses. A number of programs can check a computer for viruses. You should have such a program on your home computer, and check any floppy disk that has been used on another computer before you open any of its files. It is particularly important to do this if the other computer (or transferred data) is accessible to many other people.
One should also make copies regularly of all important programs and information. This prevents a loss of data if a destructive virus program inadvertently runs on your computer.