Apple ceased support for the Windows version of QuickTime in 2016, and ceased support for QuickTime 7. QuickTime is an extensible multimedia framework developed by Apple Inc., capable of handling various formats of digital video, picture, sound, panoramic images, and interactivity.First made in 1991, the latest Mac version, QuickTime X, is currently available on Mac OS X Snow Leopard and newer. If you want a good video player, Quicktime is perfect for your Mac.
H.264 is perfect for videos because it allows yout o have good quality videos with minor size.
It is available for Mac and Windows and it uses the H.264 video codec, used also by any MPEG-4 HD-DVD, Blu-ray and mobile phones to play videos. It is the official video player by Apple and it also works as audio player and image viewer.
QuickTime is more than a simple video player.