A computer virus is a program that can be self-replicating and perform unauthorized actions on a computer, but requires an action to commence execution.
Viruses are generally spread in two ways:
- From files added to your computer from removable media like floppy disks
- Via email and the Internet
 Viruses (or Virii) can be dangerous from the moment they are executed. The virus can perform whatever task it was designed to perform immediately, or it can wait for a specific date. The programs that wait for a specific date can be particularly difficult to deal with, as you will not be aware of their presence until they execute. A virus is typically inactive until an infected program is run or the boot record is read. As the virus is activated, it loads into the computer's memory where it can perform a triggered event and/or spread itself. Disks used in an infected system can then carry the virus to another machine. Programs downloaded from bulletin boards and web sites can also spread viruses.
To determine whether or not a floppy disk or computer drive is infected by a virus, it is necessary to run a virus scanning utility, a program that can detect and often remove viral code. Therefore, we recommend that you run anti-virus software on your machine at all times, and that you keep updating it regularly.
Downloading attachments can be risky as they can be a source to a virus. Similarly watch out for files with the following extensions:
|
