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From human computers to computerized spreadsheets

VisiCalc demoed (privately) on an Apple II at West Coast Computer Faire on 11 May 1979.

Once upon a time, people (often women) were computers.

A “computer” was a person who made calculations. (No idea why they weren’t dubbed “calculators”!)

In the late 19th century, women “computers” at the Harvard College Observatory analyzed photographic plates to determine the movement of stars. In 1875, Edward Charles Pickering hired the first three women computers: R.T. Rogers, R.G. Saunders and Anna Winlock. Their pay and contributions to the science of astronomy were secondary to the men surrounding them.

In 1939, the Jet Propulsion Laboratory (JPL) in California hired Barbara “Barby” Canright as their first female computer.

 As the first female “human computer,” her job was to calculate anything from how many rockets were needed to make a plane airborne to what kind of rocket propellants were needed to propel a spacecraft.


Macie Roberts was about 20 years older than the other computers working at JPL… When tasked with building out her team, she made the decision to hire only women, believing men would undermine the cohesion of the group and not take direction well from a woman.

The NASA facility is managed by the nearby California Institute of Technology.

By the 1960s, NASA had begun using IBM mainframe computers but the “human computers” remained an integral part of the space program. The book and movie, Hidden Figures*, celebrates their stories.

By the 1970s, personal computers were entering the homes of hobbyists. Steve Jobs introduced the the Apple II at first annual West Coast Computer Faire in April 1977.

Two years later, on 11 May 1979 (in most accounts), Dan Bricklin and Bob Frankston demonstrated VisiCalc, a visible calculator, on an Apple II.

VisiCalc was the “original spreadsheet software” that “made a business machine of the personal computer.”

VisiCalc simplified bookkeeping by automatically calculating changes throughout a worksheet after updating a single cell.

For many users, the application best demonstrated the value of personal computers for small businesses, reducing a 20-hour-per-week bookkeeping task to a few minutes of data entry in certain circumstances.

VisiCalc was the predecessor to Excel, designed to replace manual accounting worksheets or ledgers. In 2004, Bricklin contextualized that early computing experience:

VisiCalc was a $5000 purchase, if you included a good printer. But for many people it paid for itself in the first year, or in the first month.

Imagine if a personal computer, printer and accounting software were to cost $20,000+ today. That’s $5,000 adjusted for inflation.

By 1981, VisiCalc would also run on Windows computers. Mitch Kapor, who had worked as the head of development for VisiCalc, released Lotus 1-2-3 as a native Windows application in 1983. In 1985, Lotus Development purchased and “promptly discontinued the sale of VisiCalc and the remainder of the company’s products.” The Microsoft juggernaut had begun.

* Affiliate links
** Updated with Dan’s note that the demo at the West Coast Computer Faire was private, not public.

#scitech, #computing (112/365)
📷 Wikimedia
Daily posts, 2022-2023

By Kathy E. Gill

Digital evangelist, speaker, writer, educator. Transplanted Southerner; teach newbies to ride motorcycles! @kegill

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