MAC - Who Is Darwin? (Max OS X)
Darwin is a BSD UNIX environment and is the open source foundation of Mac OS X. Darwin includes various components and technologies inherited from a number of sources, including BSD 4.4 Lite source code (more specifically, FreeBSD and NetBSD), Carnegie Mellon University's Mach microkernel project, the NEXTSTEP operating system, the OPENSTEP environment, and earlier versions of Mac OS. All widely used BSD UNIX application programming interfaces and features are provided by Darwin, so if your application is a vanilla BSD UNIX application, in many cases it will compile and run without any major modifications on Darwin. However, it's important to keep in mind that, although Darwin is the core of Mac OS X, it includes only a subset of all features provided by Mac OS X. For example, Darwin doesn't provide higher-level technologies, such as Quartz, OpenGL, QuickTime, Cocoa, and Carbon.