Advertiser pays publisher a commission for every install by a user of usually free applications bundled with adware applications. Users are prompted first if they really want to download and install this software. Pay per install is included in the definition for pay per action (like cost-per-acquisition), but its relationship to how adware is distributed made the use of this term versus pay per action more popular to distinguish it from other CPA offers that pay for software downloads. The term pay per install is being used beyond the download of adware.