Joost in an Internet television distribution system. Created by the founders of Kazaa and Skype, Joost uses P2P technology similar to those two applications. However, whereas Kazaa was designed primarily for delivering unmoderated content and Skype was designed for direct P2P interaction, Joost is designed to transmit moderated content via a transparent distribution model, as if the content were broadcast from a single central source. This simulates television's one-to-many broadcast model. As a lack of dynamic interaction with the application would likely turn away potential users, Joost incorporates a user rating and recommendation system. Also, advertisements will be interactive by interfacing directly with the advertiser's website. Joost is intended to compete with cable and satellite broadcast TV, not with video-clip archives such as YouTube. No user-generated content, with the exception of reviews and recommendations, is planned. As of late 2007, the Joost client is available for the Microsoft Windows and Macintosh operating systems. A Linux client is reported to be in the works.
Based upon P2P filesharing technology, Joost is different from other streaming media services in that media receivers also redistribute the content that they receive. This leads to reduced server load and more reliable content delivery. The system is similar to the bittorrent model, which also redistributes downloaded content to other users. However, whereas bittorrent is designed to distribute static files that will be saved after download, Joost is designed to distribute streaming files that will be erased as they are viewed. A cache may store parts of files for repeat playback or redistribution. Pause, fast-forward, and rewind features will also depend upon this cache.
Joost has paired with several video and audio content providers, with terms similar to cable-TV partnerships. Notable among Joost's partners is Viacom, who owns Paramount Pictures and MTV. Viacom is considered a key content provider for any content network, and it's agreement with Joost plants the Joost project as firm competition to traditional video providers. Warner Music and the National Hockey League have also signed contracts with Joost. In addition to content providers, Joost has over 30 major-brand advertisers signed including Coca Cola, Microsoft, Nike, and Sony.