EDSAC, the first practical electronic digital stored-program computer, runs its first operation.

The Electronic Delay Storage Automatic Calculator (EDSAC) was an early British computer. Inspired by John von Neumann's seminal First Draft of a Report on the EDVAC, the machine was constructed by Maurice Wilkes and his team at the University of Cambridge Mathematical Laboratory in England to provide a service to the university. EDSAC was the second electronic digital stored-program computer, after the Manchester Mark 1, to go into regular service.

The von Neumann architecture—also known as the von Neumann model or Princeton architecture—is a computer architecture based on the First Draft of a Report on the EDVAC, written by John von Neumann in 1945, describing designs discussed with John Mauchly and J. Presper Eckert at the University of Pennsylvania's Moore School of Electrical Engineering. The document describes a design architecture for an electronic digital computer made of "organs" that were later understood to have these components:

• a central arithmetic unit to perform arithmetic operations;
• a central control unit to sequence operations performed by the machine;
• memory that stores data and instructions;
• an "outside recording medium" to store input to and output from the machine;
• input and output mechanisms to transfer data between the memory and the outside recording medium.

May 6 is the 126th day of the year in the Gregorian calendar; 239 days remain until the end of the year.