Quartz (graphics Layer)
Quartz specifically refers to a pair of OS X technologies, each part of the Core Graphics framework: Quartz 2D and Quartz Compositor. It includes both a 2D renderer in Core Graphics and the composition engine that sends instructions to the graphics card. Because of this vertical nature, Quartz is often interchanged synonymously with Core Graphics.
In a more general sense, the term Quartz or Quartz technologies can refer to almost every part of the Mac OS X graphics model from the rendering layer down to the compositor. In this use, the term covers Core Image and Core Video as well.
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