OpenStep

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OpenStep

Developer(s)	NeXT, Sun Microsystems
Initial release	October 19, 1994; 29 years ago (1994-10-19)
Written in	Objective-C
Operating system	Solaris; Windows NT; Unix-like operating systems with the Mach kernel
Platform	IA-32, PA-RISC, SPARC
Available in	English
Type	Application programming interface
Website	www.gnustep.org/resources/OpenStepSpec/OpenStepSpec.html

OpenStep is an object-oriented application programming interface (API) specification developed by NeXT. It provides a framework for building graphical user interfaces (GUIs) and developing software applications. OpenStep was designed to be platform-independent, allowing developers to write code that could run on multiple operating systems, including NeXTSTEP, Windows NT, and various Unix-based systems. It has influenced the development of other GUI frameworks, such as Cocoa for macOS, and GNUstep.

OpenStep was principally developed by NeXT and Sun Microsystems, to allow advanced application development on Sun's operating systems, specifically Solaris. NeXT produced a version of OpenStep for its own Mach-based Unix OS, stylized in all capital letters as OPENSTEP.^[1] The software libraries that shipped with OPENSTEP are a superset of the original OpenStep specification, including many features from the original NeXTSTEP.