Napster was the name given to two music-focused online services. It was founded as a pioneering peer-to-peer (P2P) file sharing Internet service that emphasized sharing digital audio files, typically audio songs, encoded in MP3 format. The company ran into legal difficulties over copyright infringement. It ceased operations and was eventually acquired by Roxio. In its second incarnation, Napster became an online music store until it was acquired by Rhapsody from Best Buy on December 1, 2011.
Later companies and projects successfully followed its P2P file sharing example such as Gnutella, Freenet, Kazaa, BearShare, and many others. However, some services, like LimeWire, Scour, Grokster, Madster, and eDonkey2000, were brought down or changed due to copyright issues....LESS