History of the hard drive

History of the hard drive

The first hard drive was invented in early 1956, at the request of the US Air Force, by the company IBM. It was called the RAMAC 305 (with the name standing for Random Access Method of Accounting and Control), a group of 50 aluminium disks each 61 cm in diameter, turning at 3600 revolutions per minute and coated with a fine magnetic layer. It could store up to 5 million characters (5 megabytes). This drive had a transfer rate of 8.8 Kbps and weighed more than a tonne! On 10 February 1954, the RAMAC 305 was able to read and write data in succession, and became the first of what we now call Direct Access Storage Devices, or DASD.

In 1962, IBM introduced a new model, the 1301, with a capacity of 28 MB and a transfer rate and an areal density 10 times higher than the RAMAC 305. The distance between the heads and the disk surface had gone down from 20.32 µm to 6.35 µm.

Starting in 1962, several manufacturers started to sell hard drives like the 1301.

In 1965, IBM came out with the 2310, whose notable feature was a removable storage element (the first floppy disk).

The 2314, released in 1966, had ferrite (iron oxide) read heads.

In 1973, IBM released the Winchester 3340, a hard drive whose read had was separated from the surface by a thin layer of air just 0.43 µm thick. Its capacity improved upon that of the RAMAC, as did its size and weight, which made this drive the new standard for direct-access storage devices. The hard disk's 30 MB capacity earned it the nickname 30-30, and thus it became the "Winchester" (after the famous .30-30 rifle).

The first 5.25" (five-and-a-quarter inches) disk drive, developed by the company Seagate, was released in 1980.

The birth of the SCSI interface

In 1979, the company Shugart Associates, founded by Alan F. Shugart (a former IBM field engineer), perfected a parallel connection for linking hard drives to personal computers, called SASI (Shugart Associates Standard Interface). This interface became the SCSI in 1982, and was standardized by ANSI (the American National Standards Institute) in 1986.

The birth of the floppy disk

In 1967, IBM created the first floppy disk drive.

In August 1976, Shugart announced the first 5.25" floppy disk drive, at a price of $390.

In June 1982, Sony introduced its own new floppy disk format: 3.5" (three-and-a-half inch) disks.

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