M2TS (MPEG-2 Transport Stream) is a Blu-ray BDAV container format that uses MPEG-2 transport stream and comes with a .m2ts filename extension. It can manipulate audio, video, and other metadata such as disc menu and subtitles. At a bare minimum, any Blu-ray player should play M2TS files easily.
HEVC (High Efficiency Video Coding), is a modern video compression standard developed as the successor to the standard H.264 (Advanced Video Coding). In comparison to H.264, this format offers up to 50% better data compression while providing improved video quality at a similar bitrate. Today, HEVC is used by over 40% of video developers, only second to AVC.