The QuickTime Player, the application provided with macOS. QuickTime is Apple's protocol for video and media creation and playback.
QuickTime is an extensible multimedia framework developed by Apple, 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.
Apple has ceased support for the Windows version of QuickTime in 2016.