Advertising-supported software, more commonly referred to as adware, is software which automatically renders advertisements in order to generate revenue for its author. Ads may display in the user interface of the software or on a screen during the installation process.
Adware is often used by developers as a way to recoup development costs, with the income generated by ads allowing the developer to develop or upgrade the software.
The use of adware is becoming increasingly popular, with advertisement-funded software being one of the business models for open source software.
In application software, it is common for software to be offered in two ways – one as a free, advertising-supported version, and the other a paid, ad-free version. Some software developers offer adware as an alternative to software licenses, funding the development of the software with higher fees for advertisers. Adware is also a popular business model for software as a service (SaaS), with popular examples including Gmail and Facebook.
Adware is often used to describe a type of malware which displays unwanted ads to computer users. Ads produced by malicious adware often display as a pop-up or ‘unclosable’ window.