July 14, 1953 — IBM Announces the Model 650
July 14, 1953
On July 14, 1953, IBM announced the Model 650 Magnetic Drum Data Processing Machine at its laboratory in Endicott, New York. It would go on to become the best-selling computer of the 1950s and the first to earn IBM a significant profit.
A Machine Built for the Middle of the Market
By the early 1950s, IBM already sold the 701 for scientific computing and the 702 for business data processing, but both were large, expensive machines aimed at the biggest organizations. The 650 was designed as a smaller, cheaper alternative that smaller businesses, universities, and government offices could actually afford to install.
How the 650 Stored Data
The 650 was a two-address, decimal computer that stored both data and instructions as magnetized spots on a rotating drum four inches in diameter and sixteen inches long. Spinning at 12,500 revolutions per minute, the drum held 1,000, 2,000, or 4,000 ten-digit words, and a word could only be read or written once its location passed beneath the read/write heads during rotation.
IBM Badly Underestimated Demand
IBM’s own sales forecast predicted that only about 50 machines would ever be sold. That estimate proved wildly conservative: by mid-1955, more than 75 systems were already installed, and IBM was preparing to deliver hundreds more. By the time production ended in 1962, nearly 2,000 units had been built.
Why the 650 Mattered
The Model 650 is widely regarded as the world’s first mass-produced computer, and its runaway commercial success made it the first computer to generate substantial profit for its manufacturer. Because so many universities and businesses could finally afford a real computer, the 650 also played a major role in turning computer science into an academic discipline and computing into a standard business tool rather than a scientific curiosity.
Sources
Key facts
- Event date
- 1953-07-14
- Organizations
- IBM
- Technologies
- IBM 650, IBM 701, IBM 702
- Topics
- computer history, business computing
Pasha Kalashnikov