Spyware is a wide-reaching term that describes software used to monitor your Internet usage patterns, as well as software that can attempt to change your Internet browser configuration, or even record keystrokes (Virginia, the hackers want your bank account and other online passwords).
Most spyware is not malicious in the same way that viruses are, and spyware works differently than viruses do. For this reason, antivirus products do little, if anything, to protect you from spyware. Also, spyware is more of a privacy issue than it’s a security issue.
Antispyware software is used to prevent and/or remove spy-ware from your computer.