Because the existence of a malicious code sequence in computing systems has action
different by the very conception and mode of action of that code, there is a group of
in the following categories:
• Viruses;
• Worms;
• Trojans;
• Bombs;
• Trap Doors / Back Doors;
• Hoaxes;
• Other types of malicious programs.
A malicious program may, however, have, and there are many such cases,
the behavior of several types of malicious programs out of the above. Here it is believed that hybrid viruses are recorded where it is difficult to define which category they actually belong to.