Back in September 1956, IBM introduced the 305 RAMAC which was the first computer to have an integrated hard disk drive (HDD). This disk drive had the then enormous capacity of 4.4 MB, using a stack of fifty 24-inch platters with an annual lease of US$35,000 (remember, these were 1956 space dollars).
To better appreciate the size and weight of the 350 RAMAC disk drive, take a look at this picture of one being loaded onto an airliner - a forklift truck is needed to lift less than 5 MB. Wow!
Move on a decade, and by the mid-1960s we had the IBM 2311 disk storage drive which consisted of one or more washing machine sized cabinets. You would lift a cabinet lid and mount a removable disk pack with 7.25 MB capacity. Each disk control unit could support eight 2311 drives, giving a total capacity of 58 MB.
IBM has kept on introducing higher-capacity, faster, more efficient disk drives in this manner over the intervening decades - the IBM 3340, 3370, and the 3380 - the first gigabyte-capacity drives - plus quite a few more.
Of course, other vendors also made important contributions, such as (in 1980) Seagate Technology's ST506 5.25-inch, 5MB capacity hard drive for microcomputers; Rodime made the first 3.5-inch drive in 1983, and so on.
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