ChronoFive
Play today’s puzzle
Setting the scene
Business analysts still built financial models on paper ledgers and calculators; Dan Bricklin imagined an electronic spreadsheet while watching a professor redraw rows on a blackboard at Harvard Business School.
What happened
VisiCalc was released in October 1979 for the Apple II, programmed by Bob Frankston and marketed by Bricklin's Software Arts; it let users recalculate entire columns instantly.
Why it still matters
VisiCalc became the Apple II's killer app and proved software could sell hardware—paving the way for Lotus 1-2-3 and Microsoft Excel. Memorable detail: Bricklin reportedly sketched the idea on paper during a finance class before writing a line of code.
Background
Dan Bricklin and Bob Frankston invented the electronic worksheet.