The M2TS extension is used by files saved in the BDAV high definition Blu-ray format. M2TS are multimedia files based on the MPEG-2 Transport Stream container which is used for multiplexing video, audio and other streams. The Blu-ray Disc Audio Video (BDAV) file format supports resolutions of up to 1080i.
The BDAV container format is currently the industry standard for Blu-ray discs. M2TS files saved on a Blu-ray disc have a 5 digit number name (can be a date or timestamp) and are located in the STREAM sub-folder.
How to open M2TS files
M2TS files can be opened with a wide range of media players on all major operating systems but some applications may require a codec or plug-in to be installed first.