Darwin (operating system)

Darwin is an open source Unix-like operating system, first released by Apple Inc. in the year 2000. It consists of code developed by Apple, as well as code derived from NeXTSTEP, BSD, Mach and other free software projects.

Darwin forms the core of the components on which macOS (formerly OS X and Mac OS X), iOS, watchOS, tvOS, and iPadOS are based. It is mostly POSIX compliant, but has never, by itself, been certified as compliant with any version of POSIX. Starting with Leopard, macOS has been certified as compliant with the Single UNIX Specification version 3 (SUSv3).

History

Darwin's legacy began with NeXT's NeXTSTEP operating system (later, since version 4.0, known as OPENSTEP), first released in 1989. After Apple bought NeXT in 1997, it announced that it would base its next operating system in OPENSTEP. This was developed into Rhapsody in 1997, Mac OS X Server 1.0 in 1999, Mac OS X Public Beta in 2000, and Mac OS X 10.0 in 2001. In 2000, the core operating system components of Mac OS X were released as release software. open source under the Apple Public Source License (APSL) as Darwin; higher level components, such as the Cocoa and Carbon frameworks, remained closed source. The name is a tribute to the British naturalist Charles Darwin.

Until Darwin 8.0.1, Apple released an installer binary (as an ISO image) after each major release of Mac OS X that allowed Darwin to be installed on PowerPC and Intel x86 systems as a stand-alone operating system. Minor updates were released as separately installed packages. Darwin is now only available as source code, except for the ARM variant, which has not been released in any form separate from iOS, watchOS, or tvOS.