>> Type of Computer Viruses
Type of computer viruses and how they work
- Worm: A virus designed to take control of a system temporarily.
It often corrupts data and causes irreparable damage.
- Trojan horse: Usually disguised as a useful program that contains
hidden instructions to perform a malicious task instead. A Trojan
horse might even be disguised in the form of a game or a utility
programmme to attract users. Only when the computer user run the
programme will he realise that he has loaded a virus that may
erase the data on the hard disk or cause another damage.
- Time bombs/logic bombs: They are designed to sit harmlessly
on a system until a certain event or date causes the programme
to activate itself. The most famous of which is the Michelangelo
virus, named after the great artist
- File infectors: Most common virus that spreads from program
to program and do damage to code, data, and directories. A file
infector virus hidden on a floppy disk will transfer itself to
any hard disk that the floppy disk comes into contact with. When
another floppy disk is inserted into the computer containing that
hard drive, the virus will copy itself onto that floppy disk.
- Boot sector virus: This sort of viruses will load each time
the computer is booted and can isolate data stored on the disk