Malicious Code

Viruses and worms are popular programs because they make themselves popular. When viruses were constrained only to one computer, they attempted to spread by attaching themselves to every executable program that they could find. This worked out very well for the viruses, because they could piggyback onto a floppy disk with a program that was being transferred to another computer. The virus would infect the next computer, and the next computer after that. While often successful, virus propagation was slow, and floppies could be scanned for viruses.

The advent of computer networks was a computer virus writer’s dream, allowing viruses to attempt to infect every network share to which the computer was attached. This extended the virus’s ...

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