XBMC is an award-winning free and open source (GPL) software media player and entertainment hub for digital media. XBMC is available for Linux, OSX, and Windows. Created in 2003 by a group of like minded programmers, XBMC is a non-profit project run and developed by volunteers located around the world. More than 50 software developers have contributed to XBMC, and 100-plus translators have worked to expand its reach, making it available in more than 30 languages.
While XBMC functions very well as a standard media player application for your computer, it has been designed to be the perfect companion for your HTPC. Supporting an almost endless range of remote controls, and combined with its beautiful interface and powerful skinning engine, XBMC feels very natural to use from the couch and is the ideal solution for your home theater.
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Hay bastantes guías en internet acerca de la configuración paso a paso de este software, algunas exquisitas como esta guía completa de xbmc eden que explica de forma detalladísima lo que aquí contaré a grandes rasgos para no perder demasiado tiempo logueando y sí haciendo.