Any kind of software that displays advertisements while it is running. The display of adverts is sometimes incidental to the software's main purpose (e.g. a game). In the case of a piece of malware, the adverts may be its only purpose, possibly hidden behind a pretence of providing some desired function like a security scanner. The adware's distributors may get paid for every machine infected.The adverts may vary in obtrusiveness from occasional or out-of-the-way images, audio or video to blocking access to the desired function while the advert is presented. Nagware is a special case of adware where the advert is for a license for, or upgrade to, the program itself.
Last updated: 2018-12-13