Last.fm is a social networking company which revolves around its music recommendation engine. It offers events, wiki-created artist profiles and discographies and community forums. Unlike competitor Pandora, Last.fm's recommendations are not generated by matching similar musical attributes, instead it offers internet radio stations programmed by comparing user data to the rest of the Last.fm user community. This data is submitted (or "scrobbled" to use the company's terminology) via more than 600 devices and media players. Another major differentiator for Last.fm from its competitors is the extensive API offering which allows products like Spotify, SongKick, and Microsoft's XBox Kinect to use Last.fm user data to drive important features. Dozens of smaller developer have also built on the API, creating a vibrant, ad-hoc research and development community around music services exposing users playlists and favorite tracks on social networks like Facebook, Myspace, and Tumblr.