ABSTRACT
The advent of computer viruses has brought a plague into the heart of Intel-based IT over the course of recent years, which is now costing British business alone more than £100 million annually. According to a recent survey by the UK National Computing Centre, viruses have become the most common problem for British enterprises, affecting 51 percent of firms. At the outset, it is vital to understand the simple fact that a virus is just a computer program, a piece of software. Like any other software, it can be transferred from computer to computer by floppy disc, or migrate over a communications network between desktops in an office, from one corporation into another and from continent to continent. Macro viruses do not exist in the normal executable machine code of a boot sector or in an executable file like most of the file viruses.
