Complex sentence: Adware, or advertising-supported software, is software that generates revenue for its developer by automatically generating advertisements in the user interface of the software or on a screen presented to the user during the installation process.
Split into simpler sentences: Adware, or advertising-supported software, is software that automatically generates advertisements in order to generate revenue for its author. The advertisements may be in the user interface of the software or on a screen presented to the user during the installation process.