Microtransaction is a business model where users can purchase virtual goods via micropayments. Microtransactions are often used in free-to-play games to provide a revenue source for the developers. While microtransactions are a staple of the mobile app market, they are also available on traditional computer platforms such as Valve Corporation's Steam platform.Free-to-play games that include a microtransaction model are sometimes referred to as "freemium".