NEXTSTEP

NEXTSTEP was the original object-oriented, multitasking operating system that NeXT Computer developed to run on its proprietary NeXT computers ("black boxes") such as the NeXTcube. NEXTSTEP 1.0 was released on September 18, 1989 after several previews starting in 1986. The last version, 3.3, was released in early 1995, by which time it ran not only on Motorola 68000 family processors, but also IBM PC compatible x86, Sun SPARC, and HP PA-RISC. Apple Inc.'s Mac OS X is a direct descendant of NEXTSTEP.

NEXTSTEP was a combination of several parts:

a Unix operating system based on the Mach kernel, plus source code from BSD Unix
Display PostScript and a windowing engine
the Objective-C language and runtime
an object-oriented (OO) application layer, including several "kits"
development tools for the OO layers
The key to NEXTSTEP's fame were the last three items. The toolkits offered incredible power, and were used to build all of the software on the machine. Distinctive features of the Objective-C language made the writing of applications with NEXTSTEP far easier than on many competing systems, and the system was often pointed to as a paragon of computer development, even a decade later.

NEXTSTEP's user interface was refined and consistent, and introduced the idea of the Dock, carried through OpenStep and into Mac OS X, and the Shelf. NEXTSTEP also created or was among the very first to sport a large number of other GUI concepts now common in other operating systems: 3D "chiseled" widgets, 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 ("inspectors"), window modification notices (such as the saved status of a file), etc. The system was 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 in a consistent manner across all applications.

Additional kits were added to the product line to make the system more attractive. This included Portable Distributed Objects (PDO), which allowed easy remote invocation, and Enterprise Objects Framework, a powerful object-relational database system. These kits made the system particularly interesting to custom application programmers, and NEXTSTEP had a long history in the financial programming community.