MPEG-2
From MythTV Official Wiki
MPEG-2 (1994) is the designation for a group of coding standards for digital audio and video, agreed upon by MPEG (Moving Pictures Experts Group), and published as the ISO/IEC 13818 international standard. MPEG-2 is typically used to encode audio and video for broadcast signals, including direct broadcast satellite and Cable TV. MPEG-2, with some modifications, is also the coding format used by standard commercial DVD movies [1].
In the US, ATSC, CableCARD, FireWire, and QAM tuners produce MPEG-2 recordings. Due to its relative simplicity, almost any computer sold since circa 2005 can play MPEG-2 recordings from such sources with a supported video card with good drivers, such as those made by Nvidia.