A computer virus is small block of coded instructions to obtain control of PC’s CPU and directs it to perform unusual and often destructive actions. They are of types -
- BOOT INFECTORS
- SYSTEM INFECTORS
- GENERAL EXECUTABLE PROGRAM INFECTORS
A worm is a destructive program that is designed to adulterate database either all at once or over a period of time. It is very similar to the logic bomb.
HOW DO VIRUSES SPREAD?
Viruses spread through floppies, e-mails, Internet downloads and other networks.
PREVENTIVE MEASURES AND TREATMENT
There are various things one can do to prevent viral infection in a computer system. These are
- Sharing of software so as to limit the information flow.
- Limit transitivity
- Limit functionality
- Use the scanner and virus remover
- Observe whether the working of computer system is slowing down
- Watch for unusually large sizes on program files
- Watch for unusual displays on the computer screen
- Make sure that there is virus protection software on local hosts, application and file servers.