There are many kinds of spyware, but the most common is most likely adware. Adware is a type of software application that is used to track a user's online activity and screen advertisements. It can be set up on a computer system without the user's understanding, and it can be difficult to eliminate. https://thumbpower.org/?p=724 Other common types of spyware include keyloggers, which are used to track a user's keystrokes, and Trojans, which are used to steal individual info.