The art-deco enclosure for this 2½ ton computer held 5,000 vacuum tubes that were all hand-wired and air-cooled. It was used by many RAND researchers, including Artificial Intelligence pioneers Newell, Shaw, and Simon.


The RAND Corporation’s JOHNNIAC was based on the stored-program computer developed at Princeton’s IAS—and named for John von Neumann, godfather of the IAS project.

Used for scientific and engineering calculations, the JOHNNIAC was completed in 1954, though it was repeatedly expanded and improved throughout its 13-year lifespan.

JOHNNIAC elapsed hour meter panel

JOHNNIAC had run for 51,349 hours when it was finally decommissioned in 1966 after 13 years of operation. The “heater voltage” meter is higher because, to avoid failures, the vacuum tubes were left on even when the machine was not used.

View Artifact Detail
JOHNNIAC user console

JOSS, the JOHNNIAC Open-Shop System, allowed up to 10 users to access the machine interactively using a simplified programming language. It was implemented by Cliff Shaw as a “helpful assistant” for mathematicians.

View Artifact Detail
JOHNNIAC's core memory

JOHNNIAC’s experimental Selectron tube memory, built by RCA, proved unreliable. Engineers replaced it with core memory from International Telemeter Corporation, a subsidiary of Hollywood's Paramount Pictures.

View Artifact Detail
JOHNNIAC in operation

JOHNNIAC, seen near the end of its 13-year life. John von Neumann, whose picture hangs nearby, protested having the computer named after him. He was overruled by engineer John Williams, who observed, “there are lots of Johns in the world.”

View Artifact Detail
JOHNNIAC goes to a museum

JOHNNIAC is disassembled for travel to its first museum home, the Los Angeles County Museum. The Computer Museum in Boston rescued it from the County Museum parking lot in 1989 just weeks before it was to become landfill.

View Artifact Detail
Nelson Lucas at a JOSS console

Nelson Lucas, modeling typical engineer attire, was a RAND draftsman and a JOHNNIAC user. He also worked on the RAND graphics tablet.

View Artifact Detail
1 2 3 4 5 6 7
JOHNNIAC maintenance console

JOHNNIAC’s maintenance console was a window used to diagnose faults in its inner workings. Reliability was good; project engineer Bill Gunning later said, “It was a very solid machine compared to the [IBM] 701 which was in the room next door.”

View Artifact Detail
JOHNNIAC printer

JOHNNIAC used a high-speed 140-column rotating-drum printer made by the engineering firm Anderson-Nichols. It was both faster and wider than others of the time.

View Artifact Detail
RAND campus

Originally established by the US Air Force with the Douglas Aircraft Company after WWII, Project RAND became the RAND Corporation in 1948. Its proximity to the beach in Santa Monica, California was a distinct advantage for employees.

View Artifact Detail