Sony Computer Entertainment is best known for producing the popular line of PlayStation consoles. The line grew out of a failed partnership with Nintendo. Originally, Nintendo requested for Sony to develop an add-on for its console that would play Compact Discs. In 1991 Sony announced the add-on, as well as a dedicated console known as the "Play Station." However, a disagreement over software licensing for the console caused the partnership to fall through. Sony then continued the project independently.