EDSAC Runs First Program Calculating Table of Squares

EDSAC Runs First Program Calculating Table of Squares

From Science History - Daily by Inception Point Ai

June 8, 2026 · 3 min

About this episode

The episode discusses the significance of EDSAC running its first program on June 8, 1949, marking a pivotal moment in computing history.

# The Birth of the Computer Bug: June 8, 1949 On June 8, 1949, something delightfully ironic happened in the world of early computing that would forever change how we talk about computer problems. While the famous "first computer bug" story involving Grace Hopper's moth is often misdated to this day, June 8, 1949 marks a significant moment in the development of **EDSAC** (Electronic Delay Storage Automatic Calculator) at Cambridge University, when it successfully ran its first practical program. The EDSAC, built by a team led by Maurice Wilkes at the University of Cambridge's Mathematical Laboratory, was one of the world's first stored-program computers. What made June 8th special was that this was when the machine executed its first working program that actually calculated a table of squares—a simple task by modern standards, but revolutionary for its time. Picture this: a massive machine occupying an entire room, with over 3,000 vacuum tubes glowing ominously, mercury delay lines serving as memory (yes, liquid mercury!), and paper tape readers clicking away. The room would have been uncomfortably warm from all that electronic equipment, filled with the distinctive smell of hot…

Topics covered

  • early computing
  • EDSAC
  • computer history
  • programming
  • stored-program computers

Keywords

  • EDSAC
  • first program
  • computer bug
  • Maurice Wilkes
  • June 8, 1949
  • stored-program computer
  • Cambridge University

Mentioned in this episode

Organizations: University of Cambridge, EDSAC

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