Computer History Museum Visit Traces Personal Computing From ENIAC to Xerox Alto

The museum building was completed in 1995 and was originally a Silicon Graphics office campus; CHM bought it in 2002. Silicon Graphics machines are now part of the collection. The article says the exhibition covers 2,000 years of computing history, with the section on the decades around the birth of the personal computer drawing particular attention.

ENIAC was publicly unveiled in 1946 and was built by John Mauchly and J. Presper Eckert's team at the University of Pennsylvania, initially to calculate artillery firing tables for the U.S. Army. The machine used about 18,000 vacuum tubes and occupied a large room; CHM displays only part of it. Early ENIAC tasks required rewiring and resetting switches, and preparation could take days. The article says six women, who had worked on ballistic calculations, were selected to program the machine by studying its structure, designing calculation flows and tracing errors through wiring and switches. At ENIAC's first public demonstration in 1946, the six women programmers were not invited to the celebratory dinner and were not formally introduced. In 1997, they were inducted into the Women in Technology International Hall of Fame. A small ENIAC on a Chip, made by the University of Pennsylvania in 1995 for the machine's 50th anniversary, reimplements the original computing architecture on a single chip.

IBM launched the IBM 1401 in 1959 for business data processing, and the article describes it as more affordable than earlier large computers, allowing more mid-sized companies to use computers for payroll, inventory and billing. The article recounts a launch story in IBM's history: the only working prototype remained in the laboratory, so IBM built empty cabinets, used battery-driven lights and had an engineer behind them turn tape reels, demonstrating the machine to customers by closed-circuit television. Orders exceeded 5,200 in the first five weeks, more than IBM's forecast for the product's entire lifecycle. In the Demo Lab, punch cards, card readers, tape storage and printers illustrate batch processing. CHM's restoration team spent years finding parts and tracing circuits, with retired IBM engineers and volunteers taking part; a system used until 1995 at a family business in Connecticut became an important basis for the restoration.

DEC showed a PDP-1 prototype in 1959 and began deliveries in 1960. The article says the machine was still expensive research equipment, but its design emphasized real-time interaction: users could enter commands, see results and continue operating the machine rather than preparing a batch of tasks. Spacewar! was conceived in 1961 by Steve Russell, Martin Graetz and Wayne Wiitanen after they were inspired by science fiction, and Russell wrote the initial version in 1962. Two players controlled ships, turned, accelerated and fired while dealing with gravity. The article says the game was later used to show customers the machine's capabilities, with input, computation and graphics happening at the same time. CHM's Demo Lab offers play sessions at set times each month.

The article traces Xerox Alto to Douglas Engelbart's 1968 demonstration in San Francisco, later called The Mother of All Demos, which included mouse operation, text editing, hyperlinks and remote collaboration. Xerox founded PARC in 1970 to explore the future office, and the Alto appeared in 1973, three years before Apple I and eight years before the IBM PC. Its vertical screen was close to the size of a page, and its bitmap display let software control pixels, change fonts and sizes and combine text with graphics. The machine had a three-button mouse. Bravo experimented with what-you-see-is-what-you-get word processing; Smalltalk combined object-oriented programming, a graphical interface and a development environment. PARC researchers also connected machines through Ethernet to share files, send mail and use networked laser printers. The article says PARC researchers were initially reluctant to show Smalltalk to Apple during the 1979 visit, worried that other companies would take the research, but ultimately cooperated at management's request. CHM retains this disagreement and notes that Apple already had related work underway. The Alto itself was a costly research machine and was never sold commercially.

Editor's Summary

A Shaoshupai article published Oct. 24, 2026 describes a visit to the Computer History Museum in Mountain View and its exhibits on ENIAC, IBM 1401, PDP-1 and Xerox Alto. The displays document the shift from batch processing and room-sized machines to interactive research systems whose interface and networking ideas influenced later personal computers. The article also records the limited recognition given to ENIAC's six women programmers and the restoration work that keeps early machines running.