QuickTime Player for Mac supports most common video audio and image formats, works great with HD videos, and enables you to record, edit and stream Internet videos and HD movie trailers. QuickTime Player, developed by Apple, is the default video player on Mac OS system and apparently a good free option for Mac users to play videos on Mac.
Supported media formats: OGG, Flash Video, DivX Media Format, ASF, MPEG, MP3, DV-DIF, WAV, and AIFF, etc.