IBM 608 Calculator

The IBM 608 calculator was the first completely transistorized computer available for commercial installation. Announced in April 1955, the 608 began the transition of IBM's line of small and intermediate electronic calculators from vacuum tube to transistor operation. It contained more than 3,000 transistors -- tiny germanium devices no bigger than a paper clip -- and magnetic cores -- doughnut-shaped objects slightly larger than a pinhead, in the first known use of transistors and cores together in a computer. The magnetic cores could remember information indefinitely and recall it in a few millionths of a second, and made up the machine's internal storage or memory.