1949 — Cambridge University
The Electronic Delay Storage Automatic Calculator, built by Maurice Wilkes and his team, was the first practical stored-program computer. It ran its first program on May 6, 1949.
Memory used mercury delay lines: 5-foot tubes filled with mercury, where data was stored as acoustic pulses bouncing back and forth. 32 delay lines stored 512 words of 17 bits each.
EDSAC's 18-instruction set used single-letter mnemonics. It introduced the concept of a subroutine library and ran the first computer game (OXO/tic-tac-toe, 1952).