QuickDraw is the 2D graphics library and associated Application Programming Interface (API) which is a core part of the classic Mac OS operating system. It was initially written by Bill Atkinson and Andy Hertzfeld. QuickDraw still existed as part of the libraries of Mac OS X, but had been largely superseded by the more modern Quartz graphics system. In Mac OS X v10.4, QuickDraw has been officially deprecated. In Mac OS X v10.5 applications using QuickDraw cannot make use of the added 64-bit support. In Mac OS X v10.8, QuickDraw support was removed from the operating system. Applications using QuickDraw will still run under OS X 10.8; however, the current versions of Xcode and the macOS SDK do not contain the header files to compile such programs.
QuickDraw was grounded in the Apple Lisa's LisaGraf of the early 1980s and was designed to fit well with the Pascal-based interfaces and development environments of the early Apple systems. In addition, QuickDraw was a raster graphics system, which defines the pixel as its basic unit of graphical information. This is in contrast to vector graphics systems, where graphics primitives are defined in mathematical terms and rasterized as required to the display resolution. A raster system requires much less processing power however, and was the prevailing paradigm at the time that QuickDraw was developed.
QuickDraw defined a key data structure, the graphics port, or GrafPort. This was a logical drawing area where graphics could be drawn. The most obvious on-screen "object" corresponding to a GrafPort was a window, but the entire desktop view could be a GrafPort, and off-screen ports could also exist.