M2TS (MPEG-2 Transport Stream) is a digital video file format that is commonly used for high-definition video on Blu-ray discs and AVCHD camcorders. It is a container format that is used to store video, audio, and other data in a single file. M2TS files use the MPEG-2 video codec and the AC-3 or DTS audio codecs to compress video and audio data, respectively. This allows for high-quality video playback with relatively small file sizes, making it well-suited for high-definition video content. M2TS files typically contain both the video and audio streams for a particular video clip, as well as other data such as subtitles and metadata. This makes it a comprehensive format for storing and sharing high-definition video content. M2TS files can be played back on a variety of media players, including Windows Media Player, VLC, and QuickTime, and can also be converted to other more widely supported video formats like MP4 or AVI using compatible media conversion software. Overall, M2TS is a widely used video file format that provides high-quality video playback for high-definition video content, making it a popular choice for Blu-ray discs and other high-definition video applications.