The IBM System/360 mainframe was the darling and the workhorse of its day.

McKnight/AP __1964: __ IBM unveils the System/360 line of mainframe computers. It was a daring innovation that transformed business, science, government and the IT industry itself.

Computing was changing fast, which befuddled a lot of businesses. They knew they needed "electronic brains" to compete, but were reluctant to invest in more than they needed, or in systems they couldn't expand later, or that wouldn't operate well with their other computers and equipment.

In what some consider the biggest business gamble of all time, the International Business Machines Corp. invested $5 billion ($34 billion in today's dollars) in a family of six mutually compatible computers and 40 peripherals that could work together and be expanded in multiple combinations.

System/360 components included the CPU, control unit, display terminal, printer, data-cell storage, drum storage, disk storage and DASD control unit, tape storage, a tape control unit, card reader-card punch combination, console station and console typewriter.

All these elements worked with one another and with previous – and future – IBM equipment. They all used the same command set, or pretty near. The buyer could buy a small or low-performance system at low cost and upgrade later.

System/360 was the benchmark for mainframe performance for many years. It also introduced the de facto worldwide standard of the 8-bit byte, rendering 12-bit and 36-bit computers obsolete almost overnight.

The first production models weren't delivered until 1965. By 1966, IBM was selling a thousand systems a month, at $2.5 to $3 million ($20 million today) each. Big Blue's bet paid big.

Wired.com summarized the System/360's impact on its 40th anniversary:

System/360 was the world's first mainframe, and its introduction opened the door to a new era of computing in which, for the first time, it was possible to perform a million instructions per second. Even the lower-end models in the System/360 line were capable of 75,000 instructions per second.

And this newfound power, at prices most sizable businesses could afford, helped the banking and insurance industries, not to mention many others, move into a more modern age.

Indeed, author James Collins has written that the System/360, along with Ford's Model T and the Boeing 707 jet, were the three most important business innovations of all time.

It's worth noting that today's laptops are faster than the early 360s.

Source: Various

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