June 21, 1948
Manchester Baby runs first stored program
The Manchester Small-Scale Experimental Machine ran its first program on June 21, 1948 — the first program executed on an electronic stored-programA design where instructions and data share memory — programs can be loaded and changed without rewiring hardware. computer.
What it was for
Frederic Williams, Tom Kilburn, and Geoff Toothill built the Baby to test Williams tubes — a cathode-ray-tube memory. Kilburn's 17-instruction program proved instructions and data could live in the same electronic store, the model every computer uses today.
Why it's here
The Baby was the first machine to run a program stored in electronic memory.
Why it mattered
It validated stored-programA design where instructions and data share memory — programs can be loaded and changed without rewiring hardware. architecture before EDSAC and commercial computers.
What it solved
Researchers needed proof that electronic memory could hold both code and data for rewritable programs.
Media
ImageManchester Baby replicaLogg Tandy, CC BY 4.0, via Wikimedia Commons
Related
- EDSAC runs its first programsMay 6, 1949
- ENIAC formally dedicatedFebruary 15, 1946
- Claude Shannon publishes information theoryOctober 1948