The PDP–11 is a series of 16-bit minicomputers sold by Digital Equipment Corporation (DEC) from 1970 into the late 1990s, one of a set of products in the Programmed Data Processor (PDP) series. In total, around 600,000 PDP-11s of all models were sold, making it one of DEC's most successful product lines. The PDP-11 is considered by some experts to be the most popular minicomputer.
Xenix is a discontinued version of the Unix operating system for various microcomputer platforms, licensed by Microsoft from AT&T Corporation in the late 1970s. The Santa Cruz Operation (SCO) later acquired exclusive rights to the software, and eventually replaced it with SCO UNIX.
CP/M-86 was a version of the CP/M operating system that Digital Research (DR) made for the Intel 8086 and Intel 8088. The system commands are the same as in CP/M-80. Executable files used the relocatable .CMD file format. Digital Research also produced a multi-user multitasking operating system compatible with CP/M-86, MP/M-86, which later evolved into Concurrent CP/M-86. When an emulator was added to provide PC DOS compatibility, the system was renamed Concurrent DOS, which later became Multiuser DOS, of which REAL/32 is the latest incarnation. The FlexOS, DOS Plus, and DR DOS families of operating systems started as derivations of Concurrent DOS as well.
This article presents a timeline of events in the history of computer operating systems from 1951 to the current day. For a narrative explaining the overall developments, see the History of operating systems.
Coherent is a clone of the Unix operating system for IBM PC compatibles and other microcomputers, developed and sold by the now-defunct Mark Williams Company (MWC). Historically, the operating system was a proprietary product, but it became open source in 2015, released under the BSD-3-Clause license.
DESQview (DV) is a text mode multitasking operating environment developed by Quarterdeck Office Systems which enjoyed modest popularity in the late 1980s and early 1990s. Running on top of DOS, it allows users to run multiple programs concurrently in multiple windows.
The Santa Cruz Operation, Inc. was an American software company, based in Santa Cruz, California, that was best known for selling three Unix operating system variants for Intel x86 processors: Xenix, SCO UNIX, and UnixWare.
Unix System V is one of the first commercial versions of the Unix operating system. It was originally developed by AT&T and first released in 1983. Four major versions of System V were released, numbered 1, 2, 3, and 4. System V Release 4 (SVR4) was commercially the most successful version, being the result of an effort, marketed as Unix System Unification, which solicited the collaboration of the major Unix vendors. It was the source of several common commercial Unix features. System V is sometimes abbreviated to SysV.
The System 9000 (S9000) is a family of microcomputers from IBM consisting of the System 9001, 9002, and 9003. The first member of the family, the System 9001 laboratory computer, was introduced in May 1982 as the IBM Instruments Computer System Model 9000. It was renamed to the System 9001 in 1984 when the System 9000 family name and the System 9002 multi-user general-purpose business computer was introduced. The last member of the family, the System 9003 industrial computer, was introduced in 1985. All members of the System 9000 family did not find much commercial success and the entire family was discontinued on 2 December 1986. The System 9000 was based around the Motorola 68000 microprocessor and the Motorola VERSAbus system bus. All members had the IBM CSOS real-time operating system (OS) stored on read-only memory; and the System 9002 could also run the multi-user Microsoft Xenix OS, which was suitable for business use and supported up to four users.
Multiuser DOS is a real-time multi-user multi-tasking operating system for IBM PC-compatible microcomputers.
The Rainbow 100 is a microcomputer introduced by Digital Equipment Corporation (DEC) in 1982. This desktop unit had a monitor similar to the VT220 and a dual-CPU box with both 4 MHz Zilog Z80 and 4.81 MHz Intel 8088 CPUs. The Rainbow 100 was a triple-use machine: VT100 mode, 8-bit CP/M mode, and CP/M-86 or MS-DOS mode using the 8088. It ultimately failed to in the marketplace which became dominated by the simpler IBM PC and its clones which established the industry standard as compatibility with CP/M became less important than IBM PC compatibility. Writer David Ahl called it a disastrous foray into the personal computer market. The Rainbow was launched along with the similarly packaged DEC Professional and DECmate II which were also not successful. The failure of DEC to gain a significant foothold in the high-volume PC market would be the beginning of the end of the computer hardware industry in New England, as nearly all computer companies located there were focused on minicomputers for large organizations, from DEC to Data General, Wang, Prime, Computervision, Honeywell, and Symbolics Inc.
The Professional 325 (PRO-325), Professional 350 (PRO-350), and Professional 380 (PRO-380) are PDP-11 compatible microcomputers. The Pro-325/350 were introduced in 1982 and the Pro-380 in 1985 by Digital Equipment Corporation (DEC) as high-end competitors to the IBM PC.
The history of Unix dates back to the mid-1960s, when the Massachusetts Institute of Technology, AT&T Bell Labs, and General Electric were jointly developing an experimental time-sharing operating system called Multics for the GE-645 mainframe. Multics introduced many innovations, but also had many problems. Bell Labs, frustrated by the size and complexity of Multics but not its aims, slowly pulled out of the project. Their last researchers to leave Multics – among them Ken Thompson, Dennis Ritchie, Doug McIlroy, and Joe Ossanna – decided to redo the work, but on a much smaller scale.
Interactive Systems Corporation was a US-based software company and the first vendor of the Unix operating system outside AT&T, operating from Santa Monica, California. It was founded in 1977 by Peter G. Weiner, a RAND Corporation researcher who had previously founded the Yale University computer science department and had been the Ph. D. advisor to Brian Kernighan, one of Unix's developers at AT&T. Weiner was joined by Heinz Lycklama, also a veteran of AT&T and previously the author of a Version 6 Unix port to the LSI-11 computer.
FlexOS is a discontinued modular real-time multiuser multitasking operating system (RTOS) designed for computer-integrated manufacturing, laboratory, retail and financial markets. Developed by Digital Research's Flexible Automation Business Unit in Monterey, California, in 1985, the system was considered to become a successor of Digital Research's earlier Concurrent DOS, but with a new, modular, and considerably different system architecture and portability across several processor families. Still named Concurrent DOS 68K and Concurrent DOS 286, it was renamed into FlexOS on 1 October 1986 to better differentiate the target audiences. FlexOS was licensed by several OEMs who selected it as the basis for their own operating systems like 4680 OS, 4690 OS, S5-DOS/MT and others. Unrelated to FlexOS, the original Concurrent DOS system architecture found a continuation in successors like Concurrent DOS XM and Concurrent DOS 386 as well.
The Olivetti M24 is a computer that was sold by Olivetti in 1983 using the Intel 8086 CPU.
MS-DOS is an operating system for x86-based personal computers mostly developed by Microsoft. Collectively, MS-DOS, its rebranding as IBM PC DOS, and a few operating systems attempting to be compatible with MS-DOS, are sometimes referred to as "DOS". MS-DOS was the main operating system for IBM PC compatibles during the 1980s, from which point it was gradually superseded by operating systems offering a graphical user interface (GUI), in various generations of the graphical Microsoft Windows operating system.
DOS is a family of disk-based operating systems for IBM PC compatible computers. The DOS family primarily consists of Microsoft's MS-DOS and a rebranded version, IBM PC DOS, both of which were introduced in 1981. Later compatible systems from other manufacturers include DR-DOS (1988), ROM-DOS (1989), PTS-DOS (1993), and FreeDOS (1998). MS-DOS dominated the IBM PC compatible market between 1981 and 1995.
Altos Computer Systems was founded in 1977 by David G. Jackson and Roger William Vass Sr. It focused on small multi-user computers, starting with multi-user derivatives of CP/M, and later including Unix and Xenix-based machines. In its 1982 initial public offering on NASDAQ, the company raised $59M. Thereafter the company's stock was traded under the symbol ALTO.
