“The term bot is short for robot. Criminals distribute malicious software (also known as malware) that can turn your computer into a bot (also known as a zombie). When this occurs, your computer can perform automated tasks over the Internet, without you knowing it.
Criminals typically use bots to infect large numbers of computers. These computers form a network, or a botnet.
Criminals use botnets to send out spam e-mail messages, spread viruses, attack computers and servers, and commit other kinds of crime and fraud. If your computer becomes a part of a botnet, your computer might slow down and you might be inadvertently helping criminals.”
We couldn’t have explained it better. Botnets are just one of the many good reasons to keep your antivirus and antispyware up-to-date; and why you should never click on links in emails from people you don’t know. Don’t open attachments in emails unless you’re positive you know who those emails came from — and you were expecting an attachment. If you follow those suggestions, your computer will never be part of a botnet. If you don’t? Can you spell Z O M B I E?