Adware (also ad-ware, or advertising supported software) is a type of malware and is software that automatically displays advertisements, for example via pop-up windows in web browsers.

Adware as such is not dangerous and does not try to damage or take control of your computer. The adware is only aimed at making a profit for its creators. However, some adware may contain certain types of malware, such as keyloggers.

The advertising features of adware software are often designed to recognise which websites the user is on and, as a result, are able to serve ads that might be of interest to the user.

Adware can sometimes be used to obtain at least partial funding for the development of software that is otherwise distributed for free. In a sense, even shareware can be considered adware in certain cases. In some cases, adware developers offer the option of registering or purchasing the program to get rid of ads.

An interesting example of adware is the third-generation Kindle book reader, specifically ?Kindle with Special Offers.? This Kindle is sold at a significantly lower price than the classic Kindle reader, but users are presented with advertising messages in the menu.