Whirlwind I Dead
The first real-time computer — built for flight simulation, it invented magnetic core memory and became the prototype for SAGE air defense and, downstream, minicomputers.
Jay Forrester's Whirlwind was the first computer designed for speed and reliability rather than calculation — real-time response for flight simulation, then air defense. Its 16-bit word, parallel architecture, and core memory (Forrester's 1949 invention) were all firsts.
Whirlwind became the prototype for SAGE — the $8 billion defense network that trained an entire generation of engineers who went on to found the minicomputer industry.