May 11: RAM was born Today

Before I write anything, let me clarify this — By RAM I’m referring to the RAM as in ‘Random Access Memory’ and not lord Ram from the Hindu mythology! Precisely half a century ago, in 1951, Professor Jay W. Forrester applied for a patent on an important improvement in computer memory (he called it the “matrix core memory“), a ground breaking invention that would change the way people used computing, for ever.

Back when computers still weighed hundreds of pounds and were primarily used by the military, computer memory relied on cathode rays to retrieve information. But the Navy needed a faster computer that could run flight simulations in real time.

One such project, sponsored by the U.S. Navy, was Project Whirlwind at the Massachusetts Institute of Technology. The Navy wanted a computer capable of serving as a flight simulator for naval aviators. Such a computer would have to operate in “real time,” an ability no previous computer had.

Professor Forrester (born 1918) was put in charge of the project. His challenge was to devise a system of computer memory that could operate much faster than the memory then in use. Expanding on ideas he heard from colleagues, Forrester developed a system called “magnetic core memory.“

Previously, computer memory relied on cathode rays, but Project Whirlwind used a three-dimensional magnetic structure; in short, Forrester brought computer memory from the analog era into the digital age. On May 11, 1951, he applied for a patent on his invention.

The structure consisted of a plane made of wires and magnetic rings called cores. Each ring contained one bit of data. Every bit on the memory plane could be accessed with a single read-and-write cycle.

In short, magnetic core memory was the first random access memory that was practical, reliable and relatively high-speed. The time it took to request and retrieve information from memory was a microsecond — hundreds of thousands of times slower than memory today, but nonetheless a magnificent achievement in the 1950s.

Forrester applied for a patent on his invention May 11, 1951. Project Whirlwind stayed active until 1959, though the technology was never used for a flight simulator.