Napster is a name given to two music-focused online services. It was originally founded as a pioneering peer-to-peer file sharing Internet service that emphasized sharing audio files, typically music, encoded in MP3 format. The original company ran into legal difficulties over copyright infringement, ceased operations and was eventually acquired by Roxio. In its second incarnation Napster became an online music store until it merged with Rhapsody on 1 December 2011.
Later companies and projects successfully followed its P2P filesharing example such as Gnutella, Freenet and many others. Some services, like Grokster, Madster and the original eDonkey network, were brought down or changed due to similar circumstances.
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