A computer virus is a program which, after being loaded into a computer's memory, copies itself with the purpose of spreading to other computers. Most people, from the corporate level power programmer down to the computer hobbyist, have had either personal experience with a virus or know someone who has. And the rate of infection is rising monthly. This has caused a wide spread interest in viruses and what can be done to protect the data now entrusted to the computer systems throughout the world. A virus can gain access to a computer system ....