v2.3

Type 30 page: "why a round tube" section and two photos (the display, and watching Spacewar! on it, CHM). Sortable DEC family / lab-by-lab / instruction tables. Nav dividers in Ports, PDP-1 and Spacewar! menus. Digital Play (Kline et al.) framing across overview/software/ports. Extensive copy edits across the PDP-1 and DEC strands.

v2.2 — the PDP-1 strand and the DEC family

A major content build-out, with a restructured menu.

Menu: the old Code dropdown becomes The Game (Overview · Versions · The object · Play); the PDP-1 menu gains Software environment and As a games machine; a new DEC group collects the wider family.

New pages

• Spacewar! Overview — a deep-dive on the game itself: design, play, strategy, and links into every thread.
• The PDP-1 software environment — no operating system, paper tape, the assemblers, DDT, the Expensive Typewriter and TECO, and the first time-sharing.
• The PDP-1 as a games machine — Spacewar! and the honest, short story of PDP-1 play (the Minskytron, Snowflake, Munching Squares).
• The DEC PDP family — a comparative table of the whole PDP line (PDP-1 to PDP-15), word length, memory, price and notable software, with source conflicts flagged.
• PDPs at universities — which lab ran which PDP, and the foundational software (Spacewar!, time-sharing, Unix, Lisp, AI, BSD).
• The legacy of the PDP — the line forward: PDP-11 → VAX/VMS, Unix's PDP roots, the architecture's influence, DEC's later course.

Also: the Programming page's instruction-set lookup is now sortable (click a column heading) with a column glossary. Restore point; stable fast-forwarded.

v2.1 — the PDP-1 strand

Expands the site into a full PDP-1 strand, with a new top-level DEC-adjacent grouping in the menu.

New pages (PDP-1 menu):

• Programming the PDP-1 — the 18-bit word, one's-complement, the instruction set, and a live, filterable instruction-set lookup (89 entries; type a mnemonic and the table filters as you go), plus a real dispt macro quoted from the 1962 source.
• The Type 30 Display — primary-sourced from DEC's PDP-1 Handbook (F-15D) and display manuals: the Type 30 in detail, a comparative DEC display table (30/31/32/33/340), point-plot vs vector, P7 phosphor, and the light pen.
• The PDP-1 as a media machine — Peter Samson's Harmony Compiler and the four-voice 1-bit music; the arc to the Samson Box; and Raj Reddy's early speech recognition on the PDP-1 (with his 2021 CHM oral history). Embedded demos: the PDP-1 playing Boards of Canada's Olson, the Samson and Reddy oral histories.

Other: menu items renamed (PDP-1 Computer, Cambridge (UK)); the CHM PDP-1 system photo and the BBN-37 character generator on the machine page; numerous sourcing corrections.

Restore point; stable fast-forwarded to this commit.

v2.0

A major milestone. The project has grown from the v1.x project front door into a full multi-page Critical Code Studies edition of Spacewar!.

The edition

• Code / versions variorum, with recovered source per version
• Ports: the long-journey census, five port deep-dives (Cambridge, Minnesota, Stanford, MIT-AI, PDP-11), and a (provisional) descendants & diffusion section
• Restorations (CHM PDP-1, Mattis Lind's PDP-11, MiSTer FPGA, Landsteiner)
• The PDP-1 machine deep dive, and the Minskytron
• People, an interactive Timeline, Two Cultures, Why?, Bibliography, Play

Interactive

• Live Minskytron (Minsky's circle algorithm) and a live BBN-37 character generator that plots typed text dot by dot from the original 1961 glyph data
• Grouped dropdown navigation (MAIN / CODE / PORTS / PDP-1 / PEOPLE / TIMELINE)

Scholarship

• Assembler corrected to Macro (not MIDAS); the 'spacewar' vs 'Spacewar!' point; vector-vs-raster descendants history; Ed Fredkin / BBN; the CLRU's US-military funding; reorganised and partly archived sources.

Now a standalone repository (fork detached).

v1.6

A milestone release.

New pages

• Ports (the long journey census) + the port deep-dives (Cambridge, Minnesota, Stanford, MIT-AI, PDP-11)
• Restorations (CHM PDP-1, Mattis Lind's PDP-11, MiSTer FPGA, Landsteiner)
• The PDP-1 (machine deep dive: Type 30 display, paper tape, BBN/Fredkin, typeface)
• The Minskytron (Minsky's circle algorithm, live)

Navigation & infrastructure

• Grouped dropdown menu (MAIN / CODE / PORTS / PDP-1 / PEOPLE / TIMELINE), responsive
• Reorganised sources/ (canonical versions / ports/ / reference/)
• Cache-buster bumped to site.css?v=4

Content & corrections

• Descendants & diffusion section (Galaxy Game, Computer Space, Cinematronics, Taito/Sega), provisional
• Assembler corrected: Macro, not MIDAS
• Ed Fredkin, BBN/Bernie Cosell, Preonas 4.3 recollection, Tennis-for-Two/Michigan-Pool precursor footnote
• Archived the TMRC Dictionary (1959/1960)
• Rocket-exhaust colour follows ship hue; 'Barbera' spelling; vector-vs-raster history per Rousse (2015)

v1.5 — People & Two Cultures, One Campus

New in this release:

• People page (people.html): who conceived, wrote, extended, and preserved Spacewar!, with portraits and life dates; the geography of the room (the kluge room, Building 26 / the Karl Taylor Compton Laboratories, and a keyed map of the wartime Rad Lab buildings); the Tech Model Railroad Club; the unidentified "dfw"; and a "who is not here" section on the women written out of the record, after Nooney.
• Two Cultures, One Campus (two-cultures.html): the campus quarrel about what a computer was for, read as one enthusiasm for computation in two faces (the hackers and the AI academics) set against a humanist critique of it (Dreyfus, Weizenbaum, Winograd), with ELIZA as the pivot and the 1967 MacHack versus Dreyfus chess match in a footnote.
• Navigation extended across the site for the new pages.
• Bibliography: added Markoff, "A Long Time Ago, in a Lab Far Away" (New York Times, 2002).
• Corrections and a site-wide copy pass: ELIZA placed on the time-shared IBM 7094 rather than the PDP-1, Building 26 named as the Karl Taylor Compton Laboratories, and all remaining em dashes removed.

v1.4 — Minskytron display & acknowledgements

See CHANGELOG.md. The Minskytron easter egg now runs an animated, evolving rosette (circle to figure-of-eight, descending the display) with full attribution; acknowledges Norbert Landsteiner's reconstructions. stable now tracks this release.