The word adware is a word creation from the words advertisement and software
. It is software that displays advertisements in the form of advertising banners or advertising pop-ups. Adware is advertising-supporting software that automatically displays or plays advertising banners or even starts downloads. It is usually free of charge, but can be counter-financed by the banners
. In contrast to normal advertising, advertising banners displayed via adware are shown when a program is called up, when a page is changed or purely for statistical purposes and often cannot be hidden. The unauthorised display of advertising impairs the reading of web pages and is also problematic from a data protection point of view.
In addition, adware often has a code with which the user's personal information is spied on without the user's knowledge, thus fulfilling the function of spyware.