A bit of newb info going around here. Is chrome for mac. Perian is THE best video and audio codec for QuickTime Player. It includes A52, AC3 and DivX codecs which have already been mentioned. Anyone who hasnt installed the above three codecs should install Perian and you will get videos playing fine. If you have already installed the above three make sure you remove them and then install Perian (if you dont know how to remove them dont install it!). Theres also VLC which pretty much plays everything but it doesnt integrate into the system with QuickTime.

Mac QuickTime Player alternative - Free Mac Media Player. Free Mac Media Player is the perfect option when it comes to QuickTime Player for Mac. As the best free all-in-one media player for Mac users, you can free download it to watch any movie or TV shows on Mac smoothly with high quality video/audio effects. Step 3 The AVI files are then to be dragged and dropped onto the player to certify that the user gets the finest view. Conclusion: QuickTime is software that is loved by the people all over the world to play files and movies without any issue.