PLATO (computer system)


PLATO, also known as Project Plato and Project PLATO, was the first generalized computer-assisted instruction system. Starting in 1960, it ran on the University of Illinois's ILLIAC I computer. By the late 1970s, it supported several thousand graphics terminals distributed worldwide, running on nearly a dozen different networked mainframe computers. Many modern concepts in multi-user computing were first developed on PLATO, including forums, message boards, online testing, email, chat rooms, picture languages, instant messaging, remote screen sharing, and multiplayer video games.
PLATO was designed and built by the University of Illinois and functioned for four decades, offering coursework to UIUC students, local schools, prison inmates, and other universities. Courses were taught in a range of subjects, including Latin, chemistry, education, music, Esperanto, and primary mathematics. The system included a number of features useful for pedagogy, including text overlaying graphics, contextual assessment of free-text answers, depending on the inclusion of keywords, and feedback designed to respond to alternative answers.
Rights to market PLATO as a commercial product were licensed by Control Data Corporation, the manufacturer on whose mainframe computers the PLATO IV system was built. CDC President William Norris planned to make PLATO a force in the computer world, but found that marketing the system was not as easy as hoped. PLATO nevertheless built a strong following in certain markets, and the last production PLATO system was in use until 2006.

Innovations

PLATO was either the first or an earlier example of many now-common technologies:
  • Hardware
  • *. Donald Bitzer
  • *. Donald Bitzer
  • *
  • Display graphics
  • * storing in downloadable fonts.
  • *.
  • Online communities
  • *
  • * Notesfiles, 1973.
  • *
  • * Term-talk
  • * Screen software sharing:, used by instructors to help students, precursor of Timbuktu.
  • Common computer game genres, including many early realtime multi-player games
  • * Multiplayer games
  • **. Rick Blomme
  • * Dungeon games
  • **. Included the first video game boss.
  • **, likely the first graphical dungeon computer game.
  • **.
  • * Space combat
  • **
  • **
  • * Flight simulation: ; this probably inspired UIUC student Bruce Artwick to start Sublogic which was acquired and later became Microsoft Flight Simulator.
  • * Military simulations:.
  • * 3D Maze games:, based on a story by J. G. Ballard, the first PLATO 3-D walkthru maze game.
  • * Quest simulation:, like Trek with monsters, trees, treasures.
  • * Solitaire: solitaire,
  • Educational
  • *.
  • * Training systems; an ambitious ICAI programming system featuring partial-order plans, used to train Con Edison steam plant operators.

    History

Impetus

Before the 1944 G.I. Bill that provided free college education to World War II veterans, higher education was limited to a minority of the US population, though only 9% of the population was in the military. The trend towards greater enrollment was notable by the early 1950s, and the problem of providing instruction for the many new students was a serious concern to university administrators. To wit, if computerized automation increased factory production, it could do the same for academic instruction.
The USSR's 1957 launching of the Sputnik I artificial satellite energized the United States' government into spending more on science and engineering education. In 1958, the U.S. Air Force's Office of Scientific Research had a conference about the topic of computer instruction at the University of Pennsylvania; interested parties, notably IBM, presented studies.

Genesis

Around 1959, Chalmers W. Sherwin, a physicist at the University of Illinois, suggested a computerised learning system to William Everett, the engineering college dean, who, in turn, recommended that Daniel Alpert, another physicist, convene a meeting about the matter with engineers, administrators, mathematicians, and psychologists. After weeks of meetings they were unable to agree on a single design. Before conceding failure, Alpert mentioned the matter to laboratory assistant Donald Bitzer, who had been thinking about the problem, suggesting he could build a demonstration system.
Project PLATO was established soon afterwards, and in 1960, the first system, PLATO I, operated on the local ILLIAC I computer. It included a television set for display and a special keyboard for navigating the system's function menus; PLATO II, in 1961, featured two users at once, one of the first implementations of multi-user time-sharing.
The PLATO system was re-designed, between 1963 and 1969; PLATO III allowed "anyone" to design new lesson modules using their TUTOR programming language, conceived in 1967 by biology graduate student Paul Tenczar. Built on a CDC 1604, given to them by William Norris, PLATO III could simultaneously run up to 20 terminals, and was used by local facilities in Champaign–Urbana that could enter the system with their custom terminals. The only remote PLATO III terminal was located near the state capitol in Springfield, Illinois at Springfield High School. It was connected to the PLATO III system by a video connection and a separate dedicated line for keyboard data.
PLATO I, II, and III were funded by small grants from a combined Army-Navy-Air Force funding pool. By the time PLATO III was in operation, everyone involved was convinced it was worthwhile to scale up the project. Accordingly, in 1967, the National Science Foundation granted the team steady funding, allowing Alpert to set up the Computer-based Education Research Laboratory at the University of Illinois Urbana–Champaign campus. The system was capable of supporting 20 time-sharing terminals.

Multimedia experiences (PLATO IV)

In 1972, with the introduction of PLATO IV, Bitzer declared general success, claiming that the goal of generalized computer instruction was now available to all. However, the terminals were very expensive. The PLATO IV terminal had several major innovations:
  • Plasma Display Screen: Bitzer's orange plasma display, incorporated both memory and bitmapped graphics into one display. The display was a 512×512 bitmap, with both character and vector plotting done by hardwired logic. It included fast vector line drawing capability, and ran at 1260 baud, rendering 60 lines or 180 characters per second. Users could provide their own characters to support rudimentary bitmap graphics.
  • Touch panel: A 16×16 grid infrared touch panel, allowing students to answer questions by touching anywhere on the screen.
  • Microfiche images: Compressed air powered a piston-driven microfiche image selector that permitted colored images to be projected on the back of the screen under program control.
  • A hard drive for Audio snippets: The random-access audio device used a magnetic disc with a capacity to hold 17 total minutes of pre-recorded audio. It could retrieve for playback any of 4096 audio clips within 0.4 seconds. By 1980, the device was being commercially produced by Education and Information Systems, Incorporated with a capacity of just over 22 minutes.
  • A Votrax voice synthesizer
  • The Gooch Synthetic Woodwind, a synthesizer that offered four-voice music synthesis to provide sound in PLATO courseware. This was later supplanted on the PLATO V terminal by the Gooch Cybernetic Synthesizer, which had sixteen voices that could be programmed individually, or combined to make more complex sounds.
Bruce Parello, a student at the University of Illinois in 1972, created the first digital emojis on the PLATO IV system.

Influence on PARC and Apple

Early in 1972, researchers from Xerox PARC were given a tour of the PLATO system at the University of Illinois. At this time, they were shown parts of the system, such as the Insert Display/Show Display application generator for pictures on PLATO ; the Charset Editor for "painting" new characters ; and the Term Talk and Monitor Mode communications programs. Many of the new technologies they saw were adopted and improved upon, when these researchers returned to Palo Alto, California. They subsequently transferred improved versions of this technology to Apple Inc.

CDC years

As PLATO IV reached production quality, William Norris became increasingly interested in it as a potential product. His interest was twofold. From a strict business perspective, he was evolving Control Data into a service-based company instead of a hardware one, and was increasingly convinced that computer-based education would become a major market in the future. At the same time, Norris was troubled by the unrest of the late 1960s, and felt that much of it was due to social inequalities that needed to be addressed. PLATO offered a solution by providing higher education to segments of the population that would otherwise never be able to afford a university education.
Norris provided CERL with machines on which to develop their system in the late 1960s. In 1971, he set up a new division within CDC to develop PLATO "courseware", and eventually many of CDC's own initial training and technical manuals ran on it. In 1974, PLATO was running on in-house machines at CDC headquarters in Minneapolis, and in 1976, they purchased the commercial rights in exchange for a new CDC Cyber machine.
Image:Plato ist2 terminal.jpg|thumb|Using the CDC Plato network, -1980, with an IST-II terminal
CDC announced the acquisition soon after, claiming that by 1985, 50% of the company's income would be related to PLATO services. Through the 1970s, CDC tirelessly promoted PLATO, both as a commercial tool and one for re-training unemployed workers in new fields. Norris refused to give up on the system, and invested in several non-mainstream courses, including a crop-information system for farmers, and various courses for inner-city youth. CDC even went as far as to place PLATO terminals in some shareholder's houses, to demonstrate the concept of the system.
In the early 1980s, CDC started heavily advertising the service, apparently due to increasing internal dissent over the now $600 million project, taking out print and even radio ads promoting it as a general tool. The Minneapolis Tribune was unconvinced by their ad copy and started an investigation of the claims. In the end, they concluded that while it was not proven to be a better education system, everyone using it nevertheless enjoyed it, at least. An official evaluation by an external testing agency ended with roughly the same conclusions, suggesting that everyone enjoyed using it, but it was essentially equal to an average human teacher in terms of student advancement.
Of course, a computerized system equal to a human should have been a major achievement, the very concept for which the early pioneers in CBT were aiming. A computer could serve all the students in a school for the cost of maintaining it, and wouldn't go on strike. However, CDC charged $50 an hour for access to their data center, in order to recoup some of their development costs, making it considerably more expensive than a human on a per-student basis. PLATO was, therefore, a failure as a profitable commercial enterprise, although it did find some use in large companies and government agencies willing to invest in the technology.
An attempt to mass-market the PLATO system was introduced in 1980 as Micro-PLATO, which ran the basic TUTOR system on a CDC "Viking-721" terminal and various home computers. CDC itself introduced the Model 110 microcomputer running CP/M, capable of accessing PLATO and marketed to education alongside small business. Versions were built for the TI-99/4A, Atari 8-bit computers, Zenith Z-100 and, later, Radio Shack TRS-80, and IBM Personal Computer. Micro-PLATO could be used stand-alone for normal courses, or could connect to a CDC data center for multiuser programs. To make the latter affordable, CDC introduced the Homelink service for $5 an hour.
Norris continued to praise PLATO, announcing that it would be only a few years before it represented a major source of income for CDC as late as 1984. In 1986, Norris stepped down as CEO, and the PLATO service was slowly killed off. He later claimed that Micro-PLATO was one of the reasons PLATO got off-track. They had started on the TI-99/4A, but then Texas Instruments pulled the plug and they moved to other systems like the Atari, who soon did the same. He felt that it was a waste of time anyway, as the system's value was in its online nature, which Micro-PLATO lacked initially.
Bitzer was more forthright about CDC's failure, blaming their corporate culture for the problems. He noted that development of the courseware was averaging $300,000 per delivery hour, many times what the CERL was paying for similar products. This meant that CDC had to charge high prices in order to recoup their costs, prices that made the system unattractive. The reason, he suggested, for these high prices was that CDC had set up a division that had to keep itself profitable via courseware development, forcing them to raise the prices in order to keep their headcount up during slow periods.