What PLATO was
PLATO — Programmed Logic for Automatic Teaching Operations — was a computer-based education system developed at the University of Illinois from 1960 onward. By the mid-1970s, it had grown into a network of thousands of terminals connected to Control Data Corporation mainframes, accessible to students and researchers at universities across the United States and eventually worldwide. Its purpose was educational — it was designed to deliver coursework, tests, and tutorials. What it became, in practice, was something much stranger.
The students who used PLATO terminals for coursework quickly discovered that the system was a general-purpose computing environment, not a locked-down educational appliance. They could write programs, store data, and — critically — communicate with other users in real time across the network. The tools they built in the early 1970s included what are now recognisable as: instant messaging (Talkomatic, 1973), online forums (TERM-talk, then Notes, 1973–1975), multi-user chat rooms (Group Notes, 1976), and email. These were not crude prototypes. Notes, the PLATO forum system, had threaded discussions, attachments, and user profiles — features that consumer internet forums took until the 1990s to match.
The games
The games that appeared on PLATO through the 1970s were, by any standard, extraordinary. Empire (1973) was a real-time strategy game with a persistent world that multiple players competed over simultaneously — the direct ancestor of every online strategy game since. Spasim (1974) was a first-person 3D space combat game supporting up to 32 simultaneous players across multiple connected PLATO systems. Avatar (1979) was a graphical dungeon crawler with persistent characters that players developed over months of play. Moria (1975) was a text-based dungeon exploration game with persistent character advancement — the direct ancestor of the CRPG genre.
These games were not primitive experiments. Empire's game state was persistent across sessions — the world continued to evolve when individual players were offline. Avatar had a graphical interface with animated sprites, multiple player characters sharing the same dungeon, and a structured narrative with quests and objectives. Oubliette (1977) had a party-based system, multiple character classes, a generated dungeon, and a town for rest and resupply — the complete CRPG template, years before Wizardry or Ultima.
The influence and the obscurity
The influence of PLATO games on the commercial industry is direct and well-documented by the people who made the influential games. Richard Garriott has credited the PLATO Akalabeth/dungeon games as influences on Ultima. Andrew Greenberg and Robert Woodhead explicitly cited the PLATO game Oubliette as the primary inspiration for Wizardry. The creators of the original Rogue — a game that defined an entire genre — were PLATO users. The dungeon-crawling RPG as a commercial genre is, at a deep level, a commercialisation of the PLATO tradition.
Why is PLATO almost entirely absent from mainstream gaming history? The answer is access. PLATO terminals were in universities and research institutions. The games were free to users who had institutional access and completely inaccessible to anyone who didn't. There was no commercial distribution, no press coverage in hobby magazines, no way for the average person interested in games to encounter what was being built on the network. The communities that formed around PLATO games were real and lasting — some of the friendships formed in Empire and Avatar persisted for decades — but they were invisible to the outside world.
The lesson of PLATO
PLATO demonstrates something important about the relationship between technology and culture: the ideas that define a medium often appear long before the hardware exists to make them commercially viable. Massively multiplayer online games, persistent worlds, online communities, user-generated content — all of these were fully realised on PLATO in the 1970s, a quarter-century before they became mainstream.
The people who built them were students and researchers who had access to unusual computational resources and the freedom to use them as they chose. They built what they wanted to play and talk about, without commercial constraints or market research. The result was a set of innovations that the commercial industry spent the next thirty years rediscovering, each time treating them as new.
The history of PLATO is now reasonably well documented, thanks partly to Brian Dear's 2017 book The Friendly Orange Glow. But it remains a footnote in popular gaming history, which tends to trace lineages through commercial products rather than academic systems. The footnote deserves to be a chapter.