spyware v. adware
Monday, July 5, 2010 Spyware is any malicious software that collects information about a user without her knowledge. Spyware is usually distributed as a hidden component of a deliberately installed program. The program’s licensing agreement may mention that spyware is being installed, but since most EULAs are lengthy and abstruse, these warnings are rarely heeded. By monitoring keystrokes and computer usage, spyware can collect email addresses, passwords, credit card numbers, chat history, and other personal data, and send them to another party. Spyware may also install additional software or browser toolbars, slow down connection speeds and system performance, change settings, replace the user’s homepage, or redirect browser traffic.
Adware is software that automatically displays advertisements. This may be done with the user’s consent, as is the case with free, ad-supported applications. More often, however, the term adware is applied to a type of spyware that displays targeted advertisements, often in pop-up windows, based on a user’s browsing habits.