NeXTSTEP is a discontinued object-oriented, multitasking operating system developed by NeXT, the technology company founded by Steve Jobs. Based on the Mach kernel and the UNIX-derived BSD, it was introduced in 1989 for the company's computers before being ported to several other computer architectures. Following NeXT's transition away from hardware, version 4 was released as OPENSTEP for Mach, named after the company's OpenStep application programming interface (API).

Although relatively unsuccessful at the time, NeXTSTEP is notable for its influence on software development and computing history. Tim Berners-Lee developed the first web browser and web server on a NeXTSTEP workstation, while id Software used the operating system during development of Doom and Quake.

In 1996, Apple Computer acquired NeXT and used OPENSTEP for Mach as the foundation for Mac OS X (later macOS). Its technologies continue to form the basis of Darwin, the core operating system underlying macOS, iOS, iPadOS, watchOS, and tvOS.

Overview NeXTSTEP (also stylized as NeXTstep, NeXTStep, and NEXTSTEP) is a combination of several parts: a Unix operating system based on the Mach kernel, plus BSD Display PostScript and a proprietary windowing engine the Objective-C language and runtime an object-oriented (OO) application layer, including several "kits" development tools for the OO layers.

NeXTSTEP is an implementation of the latter three components. Its toolkits serve as the primary development system for software on the platform.

It introduced the idea of the Dock (carried through OpenStep and into macOS) and the Shelf. NeXTSTEP originated or innovated many other GUI concepts which became common in other operating systems: 3D chiseled widgets, large full-color icons, system-wide drag and drop of a wide range of objects beyond file icons, system-wide piped services, real-time scrolling and window dragging, properties dialog boxes called "inspectors", and window modification notices (such as the saved status of a file). The system is among the first general-purpose user interfaces to handle publishing color standards, transparency, sophisticated sound and music processing (through a Motorola 56000 DSP), advanced graphics primitives, internationalization, and modern typography, consistently across all applications.

Additional kits were added to the product line. These include Portable Distributed Objects (PDO), which allow easy remote invocation, and Enterprise Objects Framework, an object-relational database system. The kits made the system particularly interesting to custom application programmers, and NeXTSTEP had a long history in the financial programming domain.

History NeXTSTEP was built on the Mach kernel and the Unix-derived BSD, initially 4.3BSD-Tahoe. A preview release (version 0.8) was shipped with the NeXT Computer on October 12, 1988, and the first commercial release, NeXTSTEP 1.0, was made available on September 18, 1989. Later releases incorporated newer BSD code, including 4.3BSD-Reno in NeXTSTEP 3.0.

NeXTSTEP was initially released for NeXT's Motorola 68000-based workstations. As the company transitioned away from hardware, NeXTSTEP 3.3, released in early 1995, was ported to x86, SPARC, and PA-RISC.

As part of this transition, NeXT partnered with Sun Microsystems to develop the OpenStep specification, separating the application frameworks from the underlying operating system so they could be implemented on multiple platforms.

With the introduction of the OpenStep specification, NeXT rebranded NeXTSTEP as OPENSTEP for Mach, its implementation of the specification that retained the existing Mach-based operating system and compatibility with NeXTSTEP applications. Versions 4.0, 4.1, and 4.2 were released between 1996 and 1997.

Following Apple's acquisition of NeXT in 1996, OPENSTEP for Mach became the basis for Rhapsody, which evolved into Mac OS X (later macOS). Its technologies continue to underpin Darwin, the foundation of macOS, iOS, iPadOS, watchOS, and tvOS.

Legacy The first web browser, WorldWideWeb, and the first app store were all invented on the NeXTSTEP platform.

Some features and keyboard shortcuts now common to web browsers originated in NeXTSTEP conventions. The basic layout options of HTML 1.0 and 2.0 are attributable to those features of NeXT's Text class.

Lighthouse Design Ltd. developed Diagram!, a drawing tool, originally called BLT (for Box-and-Line Tool) in which objects (boxes) are connected together using "smart links" (lines) to construct diagrams such a flow charts. This basic design can be enhanced by the simple addition of new links and new documents, located anywhere in the local area network, that foreshadowed Tim Berners-Lee's initial prototype that was written on NeXTSTEP in October–December 1990.

In the 1990s, the pioneering PC games Doom, Doom II, Quake, and their respective level editors were developed by id Software on NeXT machines. Other games based on the Doom engine such as Heretic and its sequel Hexen by Raven Software, and Strife by Rogue Entertainment were developed on NeXT hardware using id's tools.

Although relatively unsuccessful at the time, it attracted interest from computer scientists and researchers. It hosted the original development of the Electronic AppWrapper, invented by Jesse Tayler in the early 1990s, which was the first commercial software distribution catalog to collectively manage encryption and provide digital rights for application software and digital media (a forerunner of the modern "app store" concept).

Altsys made the NeXTSTEP application Virtuoso. Version 2 was later ported to the classic Mac OS and Windows, becoming Macromedia FreeHand version 4. The modern "Notebook" interface for Mathematica, and the advanced spreadsheet Lotus Improv, were developed using NeXTSTEP. The software that controlled MCI's Friends and Family calling plan program was developed using NeXTSTEP.

About the time of the release of NeXTSTEP 3.2, NeXT partnered with Sun Microsystems to develop OpenStep. It is the product of an effort to separate the underlying operating system from the higher-level object libraries to create a cross-platform object-oriented API standard derived from NeXTSTEP. OpenStep was released for Sun's Solaris, Windows NT, and NeXT's Mach kernel-based operating system. NeXT's implementation is called "OPENSTEP for Mach" and its first release (4.0) superseded NeXTSTEP 3.3 on NeXT, Sun, and Intel IA-32 systems.

Following an announcement on December 20, 1996, Apple Computer acquired NeXT on February 4, 1997, for $429 million. Based upon the "OPENSTEP for Mach" operating system, and developing the OpenStep API to become Cocoa, Apple created the basis of Mac OS X, and eventually of iOS, iPadOS, watchOS, and tvOS.

GNUstep is a free software implementation of the OpenStep standard.

Release history

VersionDateDistribution mediumArchitectureBasisNotes0.8October 12, 1988MO discm68k4.3BSD-TahoeFirst public preview, released with the NeXT Computer.0.8a1988MO discm68kBugfix release.0.9May 1, 1989MO discm68kIntroduced the Preferences application, interface improvements, and bundled FrameMaker, Mathematica, and additional software.1.0September 11, 1989MO discm68kAdded application termination from Workspace Manager, updated Preferences application, and interface refinements.1.0aDecember 21, 1989MO discm68kBugfix release.2.0September 18, 1990MO disc,CD-ROMm68kAdded support for the NeXTstation, NeXTcube and associated new hardware (floppy disk, CD-ROM, Fax modem, and color graphics), along with a redesigned Workspace Manager and dynamic driver loading.2.1March 25, 1991MO disc,CD-ROMm68kAdded support for NeXTdimension, TeX, improved internationalization, and bundled Lotus Improv with new systems.2.1a MO disc,CD-ROMm68kBugfix release.2.2March 25, 1992CD-ROMm68kAdded support for the NeXTstation Turbo.3.0September 8, 1992CD-ROMm68k4.3BSD-RenoIntroduced Distributed Objects, Project Builder and additional development kits; improved networking and file system compatibility.3.1May 25, 1993CD-ROMm68k, i386Added support for i386 architecture, introduced Multiple Architecture Binaries.3.2October 18, 1993CD-ROMm68k, i386Improved i386 support with SoftPC for emulating MS-DOS and Windows applications.3.3December 7, 1994 (m68k, i386)CD-ROMm68k, i386Final release under the NeXTSTEP name. Added support for PARISC and SPARC architectures.April 4, 1995 (SPARC, PARISC)PARISC, SPARC4.0 PR1September 7, 1995CD-ROMm68k, i386, PARISC, SPARCPreview of NeXTSTEP 4.0 featuring a redesigned user interface, introducing concepts later incorporated into the macOS Dock. Development discontinued in favor of OPENSTEP 4.0, which reverted to the NeXTSTEP 3.3 interface.4.0June 25, 1996CD-ROMm68k, i386, SPARCFirst release under the OPENSTEP name. Implements the OpenStep specification. Dropped support for the PA-RISC architecture.4.1October 23, 1996CD-ROMm68k, i386, SPARCBugfix release.4.2January 24, 1997CD-ROMm68k, i386, SPARCFinal OPENSTEP release, primarily consisting of bug fixes.RhapsodyOctober 13, 1997CD-ROMi386, PPC4.4BSDReleased following Apple's acquisition of NeXT, serving as the transitional operating system between OPENSTEP and Mac OS X.

Versions up to 4.1 are general releases. OPENSTEP 4.2 pre-release 2 is a bug-fix release published by Apple and supported for five years after its September 1997 release.

See also Bundle (macOS), from NeXTSTEP to macOS Miller columns, the method of directory browsing that NeXTSTEP's File Viewer uses NeXT character set

References

External links NeXTSTEP Installation Guide NeXTComputers.org

The Next Step BYTE Magazine 14–03, Object Oriented Programming with NextStep