Lisp machines were general-purpose computers designed (usually through hardware support) to efficiently run Lisp as their main software language. In a sense, they were the first commercial single-user workstations. Despite being modest in number (perhaps 7000 units total as of 1988^[1]), many now-commonplace technologies (including effective garbage collection, laser printing, windowing systems, computer mice, high-resolution bit-mapped graphics, computer graphic rendering and a number of networking innovations) were first developed on Lisp machines such as the ones used in Xerox PARC (Palo Alto Research Center). Image File history File links Dan-lispmachine. ... A BlueGene supercomputer cabinet. ... Lisp is a family of computer programming languages with a long history and a distinctive fully-parenthesized syntax. ... A programming language is an artificial language that can be used to control the behavior of a machine, particularly a computer. ... SGI O2 Workstation A computer workstation, often colloquially referred to as workstation, is a high-end general-purpose microcomputer designed to be used by one person at a time and which offers higher performance than normally found in a personal computer, especially with respect to graphics, processing power and the... In computer science, garbage collection (also known as GC) is a form of automatic memory management. ... Laser printer A laser printer is a common type of computer printer that produces high quality printing, and is able to produce both text and graphics. ... A windowing system (also windows system or window system) is a standard part of all modern computer graphical user interfaces, as opposed to command line interfaces. ... Operating a mechanical 1: Pulling the mouse turns the ball. ... Suppose the smiley face in the top left corner is an RGB bitmap image. ... Bold text // Headline text Link title This article is about the computer research center. ...

History

Historical context

Artificial intelligence (AI) computer programs of the 1960s and 1970s intrinsically required what was then considered a huge amount of computer power, as measured in processor time and memory space. The power requirements of AI research were exacerbated by the Lisp symbolic programming language, when commercial hardware was designed and optimized for assembler- and Fortran-like programming languages. At first, the cost of such computer hardware meant that it had to be shared among many users. But as integrated circuit technology shrank the size and cost of computers in the 1960s and early 1970s, and the memory requirements of AI programs started to exceed the address space of the most common research computer, the DEC PDP-10, researchers considered a new approach: a computer designed specifically to develop and run large artificial intelligence programs, and tailored to the semantics of the Lisp programming language. To keep the operating system (relatively) simple, these machines would not be shared, but would be dedicated to a single user. Garry Kasparov playing against Deep Blue, the first machine to win a chess game against a reigning world champion. ... A computer program is a collection of instructions that describe a task, or set of tasks, to be carried out by a computer. ... See the terminology section, below, regarding inconsistent use of the terms assembly and assembler. ... Fortran (previously FORTRAN[1]) is a general-purpose[2], procedural,[3] imperative programming language that is especially suited to numeric computation and scientific computing. ... Integrated circuit of Atmel Diopsis 740 System on Chip showing memory blocks, logic and input/output pads around the periphery Microchips with a transparent window, showing the integrated circuit inside. ... A BlueGene supercomputer cabinet. ... The introduction to this article provides insufficient context for those unfamiliar with the subject matter. ... The DEC logo Digital Equipment Corporation was a pioneering American company in the computer industry. ... The PDP-10 was a computer manufactured by Digital Equipment Corporation (DEC) from the late 1960s on; the name stands for Programmed Data Processor model 10. It was the machine that made time-sharing common; it looms large in hacker folklore because of its adoption in the 1970s by many... Garry Kasparov playing against Deep Blue, the first machine to win a chess game against a reigning world champion. ... Lisp is a family of computer programming languages with a long history and a distinctive fully-parenthesized syntax. ... A programming language is an artificial language that can be used to control the behavior of a machine, particularly a computer. ... An operating system (OS) is a set of computer programs that manage the hardware and software resources of a computer. ...

Initial development

One of LMI's Lambda machines

In 1973, Richard Greenblatt and Thomas Knight, programmers at MIT's AI Lab, started what would become the MIT Lisp Machine Project when they first began building a computer hardwired to run certain basic Lisp operations, rather than run them in software, in a 24-bit tagged architecture. The machine also did incremental (or "Arena") garbage collecting. More specifically, since Lisp variables are typed at runtime rather than compile time, a simple addition of two variables could take 5 times as long on conventional hardware, due to test and branch instructions. Lisp Machines ran the tests in parallel with the more conventional single instruction additions. If the simultaneous tests failed, then the result was discarded and recomputed; this meant in many cases an increase by several factors. This simultaneous checking approach was used as well in testing the bounds of arrays when referenced, and other memory management necessities (not merely garbage collection or arrays). Type checking was further improved and automated when the conventional byte word of 32-bits was lengthened to 36-bits for Symbolics 3600-model Lisp machines^[2] and eventually to 40-bits or more (usually, the excess bits not accounted for by the following were used for error-correcting codes). The first group of extra bits were used to hold type data, and the remaining bits were used to implement CDR coding (wherein the usual linked list elements are compressed to occupy roughly half the space), aiding garbage collection by reportedly an order of magnitude. A further improvement was two microcode instructions which specifically supported Lisp functions, reducing the cost of calling a function to (in some Symbolics implementations) as little as 20 clock cycles. Image File history File links Download high resolution version (1200x1600, 91 KB)A LMI Lisp machine with its disk drives still around. ... Image File history File links Download high resolution version (1200x1600, 91 KB)A LMI Lisp machine with its disk drives still around. ... Year 1973 (MCMLXXIII) was a common year starting on Monday (link will display full calendar) of the 1973 Gregorian calendar. ... Richard D. Greenblatt is an American programmer. ... Tom Knight is a senior research scientist in the MIT Artificial Intelligence Laboratory and the MIT EECS department. ... The Massachusetts Institute of Technology (MIT) is a private, coeducational research university located in Cambridge, Massachusetts. ... In computer science, garbage collection (also known as GC) is a form of automatic memory management. ... It has been suggested that this article or section be merged with Forward error correction. ... In computer science CDR coding is a compressed data representation for Lisp linked lists. ... In computer science, a subroutine (function, method, procedure, or subprogram) is a portion of code within a larger program, which performs a specific task and is relatively independent of the remaining code. ...

The first machine was called the CONS machine (named after the list construction operator cons in Lisp. Often it was affectionately referred to as the "Knight machine", perhaps since Knight wrote his master's thesis on the subject); it was extremely well-received.^{[citation needed]} It was subsequently improved into a version called CADR (a pun; in Lisp, the cadr function, which returns the second element of a list, is pronounced "kay'-der" or "kah'-der", as some pronounce the word "cadre") which was based on essentially the same architecture. About 25 of what were essentially prototype CADRs were sold within and outwith MIT for ~$50,000; it quickly became the favorite machine for hacking- many of the most favored software tools were quickly ported to it (e.g. Emacs was ported from ITS in 1975). It was so well received at an AI conference held at MIT in 1978 that DARPA began funding its development. CONS, Connection-Oriented Network Service, is one of the two OSI stack network layer protocols, the other being CLNS (Connectionless Network Service). ... Tom Knight is a senior research scientist in the MIT Artificial Intelligence Laboratory and the MIT EECS department. ... “M.S.” redirects here. ... Wikipedia does not yet have an article with this exact name. ... Emacs is a class of text editors, possessing an extensive set of features, that are popular with computer programmers and other technically proficient computer users. ... ITS, the Incompatible Timesharing System, was an early, revolutionary, and influential MIT time-sharing operating system; it was developed principally by the Artificial Intelligence Laboratory at MIT, with some help from Project MAC. ITS development was initiated in the late 1960s by those (the majority of the MIT AI Lab... The Defense Advanced Research Projects Agency (DARPA) is an agency of the United States Department of Defense responsible for the development of new technology for use by the military. ...

A fork

Symbolics' line of Lisp machines, c. 1986

In 1979, Russell Noftsker, convinced that Lisp machines had a bright future commercially due to the strength of the Lisp language and the enabling factor of hardware acceleration, made Greenblatt a proposal: they would take the technology commercial. In a counter-intuitive move for an AI Lab hacker, Greenblatt acquiesced, hoping perhaps that he could recreate the informal and productive atmosphere of the Lab in a real business, a bit like Apple Computer. These ideas and hopes were considerably different from the ones Noftsker held. The two negotiated at length, but neither would compromise. As the proposed company could only be a success with the full and undivided assistance of the AI Lab hackers as a group, Noftsker and Greenblatt decided that the fate of the enterprise was up to them, and so the choice should be left to the hackers. Image File history File links Download high resolution version (854x588, 55 KB)An array of Symbolics Lisp machines c. ... Image File history File links Download high resolution version (854x588, 55 KB)An array of Symbolics Lisp machines c. ... A screenshot of the sophisticated debugger on a Symbolics MacIvory machine. ... Apple Inc. ...

The ensuing discussions of the choice rent the lab into two factions. In February, 1979, matters came to a head. The hackers sided with Noftsker, believing that a commercial venture fund-backed company had a better chance of surviving and commercializing Lisp Machines than Greenblatt's proposed self-sustaining start-up. Greenblatt had lost the battle.

It was at this juncture, with Symbolics, Noftsker's enterprise, slowly coming together (while he was paying them a salary, he didn't actually have a building or any equipment for the hackers to work on, so he bargained with Patrick Winston that in exchange for allowing Symbolics' staff to keep working out of MIT, Symbolics would let MIT use internally and freely all the software Symbolics developed), and a disgruntled and inactive Greenblatt, that a consultant from CDC, who was trying to put together a natural language computer application with a group of West-coast hackers, came to Greenblatt, seeking a Lisp machine for his group to work with, about eight months after the disastrous conference with Noftsker. Greenblatt had decided to start his own rival Lisp machine company, but he had done nothing. The consultant, Alexander Jacobson, decided that the only way Greenblatt was going to actually start his company and build the Lisp machines that Jacobson desperately needed was if Jacobson pushed and otherwise helped Greenblatt launch his company. Jacobson pulled together business plans, a board, a partner for Greenblatt (one F. Stephen Wyle). The newfound company was named LISP Machine, Inc. (LMI), and was funded by CDC orders, via Jacobson. Patrick H. Winston is Ford Professor of Artificial Intelligence and Computer Science at the Massachusetts Institute of Technology (MIT). ... Control Data Corporation, or CDC, was one of the pioneering supercomputer firms. ...

Around this time Symbolics (Noftsker's company) began operations — it had been hindered by Noftsker's promise to give Greenblatt a year's head start, and by severe delays in procuring venture capital. Symbolics still had the major advantage that while 3 or 4 of the AI Lab hackers had gone to work for Greenblatt, a solid 14 other hackers had signed onto Symbolics, the lion's share of the AI Lab's hackers. There would be two exceptions, two AI Lab people who did not get hired by either: Richard Stallman and Marvin Minsky. Richard Matthew Stallman (often abbreviated as RMS) (born March 16, 1953) is a software freedom activist, hacker, and software developer. ... Marvin Lee Minsky (born August 9, 1927), sometimes affectionately known as Old Man Minsky, is an American cognitive scientist in the field of artificial intelligence (AI), co-founder of MITs AI laboratory, and author of several texts on AI and philosophy. ...

A screenshot of the sophisticated debugger on a Symbolics MacIvory machine.

Regardless, after a series of internal battles, Symbolics did get off the ground in 1980/1981, selling the CADR as the LM-2, while Lisp Machines, Inc. sold it as the LMI-CADR. Symbolics did not intend to produce many LM-2s, since the 3600 family of Lisp machines was supposed to ship quickly, but the 3600s were repeatedly delayed, and Symbolics ended up producing ~100 LM-2s, each of which sold for $70,000. Both companies developed second-generation products based on the CADR: the Symbolics 3600 and the LMI-LAMBDA (of which LMI managed to sell ~200). The 3600, which shipped a year late, expanded on the CADR by widening the machine word to 36-bits, expanding the address space to 28-bits^[3], and adding hardware to accelerate certain common functions that were implemented in microcode on the CADR. The LMI-LAMBDA, which came out a year after the 3600, in 1983, was compatible with the CADR (it could run CADR microcode), but there were hardware differences. Texas Instruments (TI) joined the fray when it licensed the LMI-LAMBDA design and produced its own variant, the TI Explorer. Image File history File links Download high resolution version (1024x768, 26 KB)A debugger running in the Genera development environment on a Symbolics MacIvory Lisp machine. ... Image File history File links Download high resolution version (1024x768, 26 KB)A debugger running in the Genera development environment on a Symbolics MacIvory Lisp machine. ... Lisp Machines, Inc. ... Texas Instruments (NYSE: TXN), better known in the electronics industry (and popularly) as TI, is an American company based in Dallas, Texas, USA, renowned for developing and commercializing semiconductor and computer technology. ...

Symbolics continued to develop the 3600 family and its operating system, Genera, and produced the Ivory, a VLSI implementation of the Symbolics architecture. Starting in 1987, several machines based on the Ivory processor were developed: boards for Suns and Macs, stand-alone workstations and even embedded systems (I-Machine Custom LSI, 32 bit address, Symbolics XL-400, UX-400, MacIvory II; in 1989 available platforms were Symbolics XL-1200, MacIvory III, UX-1200, Zora, NXP1000 "pizza box"). Texas Instruments shrunk the Explorer into silicon as the MicroExplorer. LMI abandoned the CADR architecture and developed its own K-Machine [2], but LMI went bankrupt before the machine could be brought to market. In biology, a genus (plural genera) is a grouping in the classification of living organisms having one or more related and morphologically similar species. ... Very-large-scale integration (VLSI) is the process of creating integrated circuits by combining thousands of transistor-based circuits into a single chip. ...

These machines had hardware support for various primitive Lisp operations (data type testing, CDR coding) and also hardware support for incremental garbage collection. They ran large Lisp programs very efficiently. The Symbolics machine was actually competitive against many commercial super mini computers, but it was never adapted for conventional purposes. Though the Symbolics Lisp Machines were also sold to some non-AI markets like computer graphics, modeling and animation. In computer science CDR coding is a compressed data representation for Lisp linked lists. ... In computer science, garbage collection (also known as GC) is a form of automatic memory management. ... Computer graphics is a sub-field of computer science and is concerned with digitally synthesizing and manipulating visual content. ...

The MIT-derived Lisp machines ran a Lisp dialect called ZetaLisp, descended from MIT's Maclisp. The operating systems were written from the ground up in Lisp, often using object-oriented extensions. Later these Lisp machines also supported various versions of Common Lisp (with Flavors, New Flavors and CLOS). ZetaLisp was the name Symbolics gave to their dialect of Lisp on their Lisp Machine models, to distinguish it from the MIT version. ... MacLisp is a dialect of the Lisp programming language. ... Common Lisp, commonly abbreviated CL, is a dialect of the Lisp programming language, standardised by ANSI X3. ... Flavors, an early object-oriented extension to Lisp developed by Howard Cannon at the MIT Artificial Intelligence Laboratory for the Lisp machine, was the first programming language to include mixins. ... Flavors, an early object-oriented extension to Lisp developed by Howard Cannon at the MIT Artificial Intelligence Laboratory for the Lisp machine, was the first programming language to include mixins. ... The Common Lisp Object System (CLOS) is the facility for object-oriented programming which is part of Common Lisp (CL). ...

BBN developed its own Lisp Machine, called Jericho, which ran a version of Interlisp. It was never marketed; frustrated, the entire AI group resigned, and were hired primarily by Xerox. So, Xerox PARC had, simultaneous with Greenblatt's own development over at MIT, developed their own Lisp machines which were designed to run InterLisp (and later Common Lisp) as well as other languages such as Smalltalk, but they failed to enter the market, and found themselves a distant third behind LMI and Symbolics. These included the Xerox 1100, aka "Dolphin" (1979); the Xerox 1132, aka "Dorado"; the Xerox 1108, aka "Dandelion" (1981); and the Xerox 1109, aka "Dandetiger"; and the Xerox 1186/6085, aka "Daybreak". The Xerox machines were a commercial failure, but they did influence the creation of Apple Computer's Macintosh. The operating system of the Xerox Lisp Machines has also been ported to a virtual machine and is available for several platforms as a product called "Medley". The Xerox Lisp Machine was well known for its advanced development environment, for its early graphical user interface and for novel applications like NoteCards (one of the first Hypertext applications). BBN Technologies (originally Bolt Beranek and Newman) is a high technology company that provides research and development services. ... Interlisp (also seen with a variety of capitalizations) was a version of the Lisp programming language originally developed in 1967 at Bolt, Beranek and Newman in Cambridge, Massachusetts. ... Xerox Corporation (NYSE: XRX) is an American document management company, which manufactures and sells a range of color and black-and-white printers, multifunction systems, photo copiers, digital production printing presses, and related consulting services and supplies. ... Bold text // Headline text Link title This article is about the computer research center. ... Interlisp (also seen with a variety of capitalizations) was a version of the Lisp programming language originally developed in 1967 at Bolt, Beranek and Newman in Cambridge, Massachusetts. ... Common Lisp, commonly abbreviated CL, is a dialect of the Lisp programming language, standardised by ANSI X3. ... For other uses, see Small Talk (disambiguation). ... Xerox Daybreak (a. ... Apple Inc. ... The first Macintosh computer, introduced in 1984, upgraded to a 512K Fat Mac. The Macintosh or Mac, is a line of personal computers designed, developed, manufactured, and marketed by Apple Computer. ... NoteCards was a hypertext system developed at Xerox PARC by Randall Trigg, Frank Halasz and Thomas Moran in 1984. ... In computing, hypertext is a user interface paradigm for displaying documents which, according to an early definition (Nelson 1970), branch or perform on request. ...

A UK company, Racal-Norsk, attempted to repurpose Norsk Data superminis as microcoded Lisp Machines, running Symbolics' ZetaLisp software. The characteristical ND dotted logo used from 1973 Norsk Data was a (mini-)computer manufacturer located in Oslo, Norway. ... A supermini can be: A car size class used in Europe. ... ZetaLisp was the name Symbolics gave to their dialect of Lisp on their Lisp Machine models, to distinguish it from the MIT version. ...

There were several attempts by Japanese manufacturers to enter the Lisp Machine market, including the Fujitsu Facom-alpha mainframe co-processor (which was actually marketed as early as 1978), and several university research efforts that produced working prototypes as part of the Fifth Generation. For the district in Saga, Japan, see Fujitsu, Saga. ... The PIM/m-1 machine, one of the few fifth generation computers ever produced The Fifth Generation Computer Systems project (FGCS) was an initiative by Japans Ministry of International Trade and Industry, begun in 1982, to create a fifth generation computer (see history of computing hardware) which was supposed...

With the onset of the "AI Winter" and the early beginnings of the "PC revolution" (which would gather steam and sweep away the minicomputer and workstation manufacturers), cheaper desktop PCs soon were able to run Lisp programs even faster than Lisp machines, without the use of special purpose hardware. Their high profit margin hardware business eliminated, most Lisp Machine manufacturers went out of business by the early 90s, leaving only software based companies like Lucid Inc. or hardware manufacturers who switched to software and services to avoid the crash. Besides Xerox, Symbolics is the only Lisp Machine company still operating today, selling the Open Genera Lisp Machine software environment as well as the Macsyma computer algebra system. To meet Wikipedias quality standards, this article may require cleanup. ... Lucid Incorporated was a supercomputer then a software development company founded by Richard P. Gabriel in 1984, which went bankrupt in 1994. ... In biology, a genus (plural genera) is a grouping in the classification of living organisms having one or more related and morphologically similar species. ... MACSYMA Reference Manual, MIT, 1977 Macsyma is a computer algebra system that was originally developed from 1967 to 1982 at MIT as part of Project MAC and later marketed commercially. ...

In the late 90s, there were plans by Sun Microsystems and other companies to build language-specific computers for Java, similar in concept and execution to the Lisp machines. Sun Microsystems, Inc. ... Java is an object-oriented applications programming language developed by Sun Microsystems in the early 1990s. ...

See also

• ICAD - (Example of "Knowledge based engineering" software originally developed on a Lisp machine that was useful enough to be then ported via Common Lisp to Unix.)
• Orphaned Technology

ICAD (Corporate history: ICAD, Inc. ... Knowledge-based engineering (KBE) is a discipline with roots in computer-aided design (CAD) and knowledge-based systems but has several definitions and roles depending upon the context. ... Common Lisp, commonly abbreviated CL, is a dialect of the Lisp programming language, standardised by ANSI X3. ... Filiation of Unix and Unix-like systems Unix (officially trademarked as UNIX®) is a computer operating system originally developed in the 1960s and 1970s by a group of AT&T employees at Bell Labs including Ken Thompson, Dennis Ritchie and Douglas McIlroy. ... Orphaned Technology is a descriptive term for computer products, programs, and platforms that have been abandoned by their original developers. ...

References

1. "LISP Machine Progress Report", Alan Bawden, Richard Greenblatt, Jack Holloway, Thomas Knight, David Moon, Daniel Weinreb, AI Lab memos, AI-444, 1977.
2. "CADR", Thomas Knight, David A. Moon, Jack Holloway, Guy L. Steele. AI Lab memos, AIM-528, 1979.
3. "Design of LISP-based Processors, or SCHEME: A Dielectric LISP, or Finite Memories Considered Harmful, or LAMBDA: The Ultimate Opcode", Guy Lewis Steele, Gerald Jay Sussman, AI Lab memo, AIM-514, 1979
4. David A. Moon. Chaosnet. A.I. Memo 628, Massachusetts Institute of Technology Artificial Intelligence Laboratory, June 1981.
5. "Implementation of a List Processing Machine". Tom Knight, Master's thesis.
6. Lisp Machine manual, 6th ed. Richard Stallman, Daniel Weinreb, David Moon. 1984.
7. "Anatomy of a LISP Machine", Paul Graham, AI Expert, December 1988
8. Free as in Freedom: Richard Stallman's Crusade for Free Software

1. ^ Newquist, Harvey. The Brain Makers, Sams Publishing, 1994. ISBN 0-672-30412-0
2. ^ "Architecture of the Symbolics 3600", David A. Moon[1]
3. ^ Moon 1985

Richard D. Greenblatt is an American programmer. ... Tom Knight is a senior research scientist in the MIT Artificial Intelligence Laboratory and the MIT EECS department. ... David A. Moon is a programmer and computer scientist, well known for his work on the Lisp programming language and related topics. ... The MIT Artificial intelligence Laboratory was an interdisciplinary research entity at MIT founded in 1959, and one of the most influential and accomplished in the field. ... Guy Lewis Steele, Jr. ... // Gerald Jay Sussman is the Panasonic Professor of Electrical Engineering at the Massachusetts Institute of Technology (MIT). ... David A. Moon is a programmer and computer scientist, well known for his work on the Lisp programming language and related topics. ... Richard Matthew Stallman (often abbreviated as RMS) (born March 16, 1953) is a software freedom activist, hacker, and software developer. ... David A. Moon is a programmer and computer scientist, well known for his work on the Lisp programming language and related topics. ... Paul Graham For Paul Graham the photographer, see Paul Graham (photographer). ...

External links

• Generic Blackboard - (Example of an AI system developed for Lisp machines)
• Symbolics
• CADR documentation
• "The Lisp Machine manual"
• "Lisp Machine Inc. K-machine: The Deffenbaugh, Marshall, Powell, Willison architecture as remembered by Joe Marshall"
• "My Lisp Experiences and the Development of GNU Emacs" - (a transcript of a speech Richard Stallman gave about Emacs, Lisp, and Lisp machines)
• "If It Works, It's Not AI: A Commercial Look at Artificial Intelligence startups"
• "Symbolics, Inc.: A failure of Heterogenous engineering" - (PDF)
• CADR simulation
• L-machine simulation
• CADR LISP Machine source code released by MIT (Oct 3 2005)
• The Explorer III Project - (A project to "develop a portable software emulator of the TI Explorer II Lisp machine.")
• Jaap Weel's Lisp Machine Webpage - (A collection of links and locally stored documents appertaining to all manner of Lisp machines)
• "A Few Things I Know About LISP Machines" - (Another collection of links, but mostly a discussion of purchasing Lisp machines)
• Ralf Möller's Symbolics Lisp Machine Museum
  • A page of screenshots of Genera
• Rainer Joswig's web page with Lisp Machine videos and screen shots
  • "Genera Concepts" - (Web copy of Symbolic's introduction to Genera)
• Vintage Computer Festival pictures of some Lisp Machines, one running Genera
• Picture of a partially disassembled Symbolics 3640
• Medley
• LISPMACHINE.NET - Lisp Books and Information
• Lisp machines timeline -(a timeline of Symbolics' and others' Lisp machines)
• [3]