Some people simply lump adware and spyware together. The two technologies do have one thing in common; they both install unwanted software on your system that can report your activities to a central location. The essential goal is the same in both cases—learning more about you and your computer habits. However, at this point, the similarities between adware and spyware end.

Adware products always installs after asking your permission, so you know about the presence of adware on your machine. (Some industry observers say that adware information purposely leaves out information you need to make a good decision—hopefully, adware vendors will correct this problem in the future.) In addition, you normally receive adware in exchange for a service or other feature of a Web site. Because adware’s purported reason to exist is to sell you products, you’ll receive constant reminders about the adware installation on your machine through the advertisements it displays. Finally, adware is normally easy to uninstall using standard techniques you use for any application. Of course, when you uninstall the adware, you also lose access to any Web site functionality that the adware supports.

Spyware products, as the name suggests, are covert. The makers of this kind of application hope to slip in under your radar so they can observe you quietly. The spyware developer hopes you won’t notice the intrusion and usually has something more personal than your buying habits in mind. For example, spyware isone technique people use to steal your identity. They gain information about you as you type passwords, account numbers, and other valuable information. Needless to say, spyware usually makes it quite hard for you to remove the software and often stores multiple copies of itself on your machine.