Quartz is the graphics layer that sits on top of the Darwin core of Mac OS X, sometimes also referred to as CoreGraphics. Quartz directly supports Aqua by displaying two-dimensional graphics to create the user interface, including on-the-fly rendering and anti-aliasing with sub-pixel precision.

There are two components that make up Quartz:

• Quartz Compositor - A compositing windowing system that manages and composites off-screen window bitmaps to create the Mac OS X user interface.
• Quartz 2D - A graphics library which uses the PDF document format to draw two-dimensional text and graphics.

External links

• Why Apple didn't use X for the window system (Mike Paquette, slashdot.org)
• Apple's Quartz page
• Apple's Quartz page for developers