AVFoundation

AVFoundation, formerly AV Foundation, is a multimedia framework with APIs in Objective-C and Swift, which provides high-level services for working with time-based audiovisual media on Apple Darwin-based operating systems: iOS, macOS, tvOS, and watchOS.

History
AV Foundation was first introduced as part of iOS 4 in 2011. It has since seen significant changes and was incorporated into other operating systems derived from iOS, such as tvOS and watchOS. Starting with Mac OS X 10.7 (Lion), it superseded QuickTime and eventually became the default media framework for the macOS platform.

AVKit
As a component of AVFoundation, AVKit is an API that is included with OS X 10.9 (Mavericks) and later and can be used with Xcode 5.0 and later for developing media player software for Macs. The AVKit software framework replaced QTKit, which was deprecated in OS X 10.9 (Mavericks) and was discontinued with the release of macOS Catalina (10.15).