SageTV Media Center, now open source, was a proprietary, commercial DVR (Digital Video Recording) and HTPC (Home theater PC) software for Mac OS X, Windows and Linux. It requires that the host computer have a hardware-based TV tuner card. The SageTV software has an integrated Electronic Programming Guide (EPG) that is updated via the Internet. The program provides a television interface for DVR, music, and photos on Windows and Linux. SageTV Media Center typically records in standard MPEG2, making it possible to transfer recordings to laptops or other devices. It also has a built-in conversion feature to transcode files into other formats compatible with iPod, PSP, cell phones and other portable devices.