QuickTime

QuickTime was a suite of multimedia features released by Apple. Its introduction came in the early days of multimedia on computers, when the possibilities of digitally-delivered multimedia were being explored. QuickTime was used as the basis of iTunes's audio and video playback functionality until version 10.5. The QuickTime movie file format (.mov) was used as the basis for the MP4 file format.

Early
Announced by John Sculley at the MacWorld San Francisco 1991 keynote, it was initially released for System 6.0.7, and later ported to Windows 3.1 in 1992. It competed with Microsoft's Video for Windows.

On 1994, Apple brought a lawsuit against San Francisco Canyon Company, which was contracted in the development of both QuickTime for Windows and Video for Windows, later adding Microsoft and Intel as defendants. The suit alleges that the company reused code developed for Apple while developing the Display Control Interface component of Video for Windows. Microsoft and Apple jointly announced the settlement of this and other disputes at the Macworld 1997 keynote.

On 1999, QuickTime 4.0 introduced support for streaming video. The release was paired with the initial release of QuickTime Streaming Server, supporting the server-side components necessary to deliver streaming content.

Mac OS X
On 2001, QuickTime 5.0 was released with support for Mac OS X.

On 2002, QuickTime 6.0 introduced support for MPEG-4 video and AAC audio.

On 2005, QuickTime 7.0 was released.

End of Life
QuickTime 7 plug-ins are not supported by its successor, AVFoundation. Given extensive professional use of QuickTime 7, QuickTime 7.6.6 remained supported as a separately installable package until macOS Catalina, which removed support for all 32-bit software. On 2016, Apple released QuickTime 7.7.9 for Windows with a security update, officially discontinuing the product with the announcement.

QuickTime Player
QuickTime Player (sometimes referred to as QuickTime X) is the modern replacement for the original QuickTime software, included with macOS starting with Snow Leopard. It bears relation to QuickTime only in name - it does not use QuickTime frameworks at all. Rather, it uses the modern AVFoundation framework (initially QTKit). It is a modern 64-bit Cocoa application, compared to the aging Carbon-based QuickTime 7 codebase. It does not support all codecs of, nor the plug-in functionality of, QuickTime 7.