Antivirus are small software programs that hopefully will spread from one computer even to another and to interfere by using computer operation.
A viral might.. corrupt or delete data off your computer, use your e-mail application to spread itself to help you other computers, or even erase everything on your hard disk.
Antivirus are often spread as a result of attachments in e-mail messages or instant messaging messages. That is why it is essential that you never open e-mail attachments should you not know who it’s from and you just are expecting it.