A virus is an actively infectious program that attaches itself onto files and
programs and alters the way a computer works. It can be destructive and erase files or it can affect how your computer works. Viruses spread through opening files or programs that have a virus attached to it. This can be done through e-mail or any other sharing of files, through floppy drives, networked machines, etc. Worms and Trojan horses are specific types of viruses. Virus Protection Software is a very important program to have on your system. It is not a part of the Windows program so it must be added to your system. Virus software is only as good as the database of viruses that it maintains. Therefore, you must update your virus software on a regular basis to keep the database current. Most Virus Protection Software packages come with a subscription to their database update service.