WTV is a format for videos recorded by Windows Media Center where video is encoded by MPEG-2, MPEG-4 or h.264 and audio – by MPEG-1 Layer II or Dolby Digital AC-3. WTV file can contain video, audio, text and other data. The container replaced DVR-MS that was used by previous versions of the Windows program. WTV supports DRM that allows protection of the content by its owner.

This format was originally created as an alternative to mp3. The idea was to achieve a small file size with better sound quality. The first versions weren’t quite successful, but with the development of AAC, it became possible to store sound with less loss of quality, and with the same file sizes as that of mp3.