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Most people are aware of threats to their computers. Viruses, Worms, and Trojans have become so common that stories about computer threats appear daily in newspapers and on television. However, you may not realise is that these threats are relatively new. Two things happened to make computer threats possible:

  • Computers became affordable and therefore common
  • The Internet allowed computers to connect easily with each other

A complete timeline of the history of computer threats can be found on Wikipedia but it is generally accepted that the first major threat was the Morris worm. This software was the first to copy itself from computer to computer, infecting all the machines with which it came in contact.

It is sometimes thought that only PCs (IBM clones) are at threat and that Apple Macintosh (Mac) and Unix systems are immune to threats such as viruses. This is not entirely true. Other computers systems are, in general, more secure than PCs. However the main reason that more PCs are affected than any other computer is that there are more PCs in the world.

As Macs and Linux machines become more common it is likely that they will be threatened by more viruses, as reported in the following article:

Next: Types of Threats