macOS, originally Mac OS X, previously shortened as OS X, is a Unix-based operating system developed and marketed by Apple since 2001. It is the primary operating system for Apple's Mac computers. Within the market of desktop and laptop computers, it is the second most widely used desktop OS, after Microsoft Windows and ahead of all Linux distributions, including ChromeOS and SteamOS. As of 2024, the most recent release of macOS is macOS 15 Sequoia, the 21st major version of macOS.
NeXTSTEP is a discontinued object-oriented, multitasking operating system based on the Mach kernel and the UNIX-derived BSD. It was developed by NeXT Computer, founded by Steve Jobs, in the late 1980s and early 1990s and was initially used for its range of proprietary workstation computers such as the NeXTcube. It was later ported to several other computer architectures.
Mac OS X Server is a series of discontinued Unix-like server operating systems developed by Apple Inc. based on macOS. It provided server functionality and system administration tools, and tools to manage both macOS-based computers and iOS-based devices, network services such as a mail transfer agent, AFP and SMB servers, an LDAP server, and a domain name server, as well as server applications including a Web server, database, and calendar server.
Darwin is the core Unix-like operating system of macOS, iOS, watchOS, tvOS, iPadOS, audioOS, visionOS, and bridgeOS. It previously existed as an independent open-source operating system, first released by Apple Inc. in 2000. It is composed of code derived from NeXTSTEP, FreeBSD, other BSD operating systems, Mach, and other free software projects' code, as well as code developed by Apple. Darwin's official mascot is Hexley the Platypus.
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.
Cocoa is Apple's native object-oriented application programming interface (API) for its desktop operating system macOS.
GNUstep is a free software implementation of the Cocoa Objective-C frameworks, widget toolkit, and application development tools for Unix-like operating systems and Microsoft Windows. It is part of the GNU Project.
Carbon was one of two primary C-based application programming interfaces (APIs) developed by Apple for the macOS operating system. Carbon provided a good degree of backward compatibility for programs that ran on Mac OS 8 and 9. Developers could use the Carbon APIs to port (“carbonize”) their “classic” Mac applications and software to the Mac OS X platform with little effort, compared to porting the app to the entirely different Cocoa system, which originated in OPENSTEP. With the release of macOS 10.15 Catalina, the Carbon API was officially discontinued and removed, leaving Cocoa as the sole primary API for developing macOS applications.
The history of macOS, Apple's current Mac operating system formerly named Mac OS X until 2011 and then OS X until 2016, began with the company's project to replace its "classic" Mac OS. That system, up to and including its final release Mac OS 9, was a direct descendant of the operating system Apple had used in its Mac computers since their introduction in 1984. However, the current macOS is a UNIX operating system built on technology that had been developed at NeXT from the 1980s until Apple purchased the company in early 1997.
OmniWeb is a discontinued web browser developed and marketed by The Omni Group exclusively for Apple's macOS operating system. Though a stable version is no longer maintained, it is still available as a free download, and unstable versions are still being released.
The Dock is a prominent feature of the graphical user interface of macOS. It is used to launch applications and to switch between running applications. The Dock is also a prominent feature of macOS's predecessor NeXTSTEP and OPENSTEP operating systems. The earliest known implementations of a dock are found in operating systems such as RISC OS and NeXTSTEP. iOS has its own version of the Dock for the iPhone and iPod Touch, as does iPadOS for the iPad.
Mac OS X 10.0 is the first major release of macOS, Apple's desktop and server operating system. It was released on March 24, 2001, for a price of $129 after a public beta.
Star Trek is the code name that was given to a secret prototype project, running a port of Macintosh System 7 and its applications on Intel-compatible x86 personal computers. The project, starting in February 1992, was conceived in collaboration between Apple Computer, who provided the majority of engineers, and Novell, who at the time was one of the leaders of cross-platform file-servers. The plan was that Novell would market the resulting OS as a challenge to Microsoft Windows, but the project was discontinued in 1993 and never released, although components were reused in other projects. The project was named after the Star Trek science fiction franchise with the slogan "To boldly go where no Mac has gone before".
XNU is the computer operating system (OS) kernel developed at Apple Inc. since December 1996 for use in the Mac OS X operating system and released as free and open-source software as part of the Darwin OS, which, in addition to being the basis for macOS, is also the basis for Apple TV Software, iOS, iPadOS, watchOS, visionOS, and tvOS.
Mac OS X Public Beta was the first publicly available version of Apple Computer's Mac OS X operating system to feature the Aqua user interface. It was released to the public on September 13, 2000 for US$ 29.95. Its release was significant as the first publicly available evidence of Apple's ability to ship the "next-generation Mac operating system" after the Copland failure. It allowed software developers and early adopters to test a preview of the upcoming operating system and develop software for it before its final release. It is the only public version of Mac OS X to have a code name not based on a big cat until the release of 10.9 Mavericks in 2013. The US version had a build number of 1H39 and the international version had build number 2E14.
Rhapsody is an operating system that was developed by Apple Computer after its purchase of NeXT in the late 1990s. It is the fifth major release of the Mach-based operating system that was developed at NeXT in the late 1980s, previously called OPENSTEP and NEXTSTEP. Rhapsody was targeted to developers for a transition period between the Classic Mac OS and Mac OS X. Rhapsody represented a new and exploratory strategy for Apple, more than an operating system, and runs on x86-based PCs and on Power Macintosh.
The spinning pinwheel is a type of progress indicator and a variation of the mouse pointer used in Apple's macOS to indicate that an application is busy.
The architecture of macOS describes the layers of the operating system that is the culmination of Apple Inc.'s decade-long research and development process to replace the classic Mac OS.
Mac operating systems were developed by Apple Inc. in a succession of two major series.
Mac OS is the series of operating systems developed for the Macintosh family of personal computers by Apple Computer, Inc. from 1984 to 2001, starting with System 1 and ending with Mac OS 9. The Macintosh operating system is credited with having popularized the graphical user interface concept. It was included with every Macintosh that was sold during the era in which it was developed, and many updates to the system software were done in conjunction with the introduction of new Macintosh systems.
