HTPC means Home Theatre Personal Computer
An HTPC is a computer equipped to play video footage and audio. An HTPC is usually used in a home-like atmosphere for displaying movies, it is a home cinema. You can tinker with a HTPC yourself, but you can also buy them ready for you. It is often a small and quiet device that has enough power to play movies. An HTPC offers a flexible system that can play more than just movies: with the right software and settings it can serve as a server, or download movies. Many HTPC systems use the free XBMC software.