A prototype unit shipped in late 1960 was the first disk drive to use one head per surface flying on a layer of compressed air as in the older head design of the IBM 350 disk storage (RAMAC). Production 353s used self-flying heads essentially the same as those of the 1301.

Informed by Jacob Rabinow’s ideas at NBS, IBM developed and shipped the first commercial Hard Disk Drive (HDD), the Model 350 disk storage unit, to Zellerbach Paper, San Francisco in June 1956 as part of the IBM 305 RAMAC (Random …

Jul 2, 2024 · Without HDDs, modern computing wouldn’t be possible, and when the IBM 350 was introduced in 1956, it jump-started a revolution in data storage. Here are a few strange facts about the IBM RAMAC’s 350 “disk storage unit” and its extraordinary impact on computing.

IBM’s RAMAC (Random Access Method of Accounting and Control) magnetic disk drive pioneered this ability. The RAMAC 350 storage unit could hold the equivalent of 62,500 punched cards: 5 million characters (about 3.75 MB).

The IBM System/360 (S/360) is a family of mainframe computer systems announced by IBM on April 7, 1964, [1] and delivered between 1965 and 1978. [2] System/360 was the first family of computers designed to cover both commercial and scientific applications and a complete range of applications from small to large.

"The 350 disk memory unit was the first hard drive. It permitted random access to any of the million characters distributed over both sides of 50 two-foot-diameter disks. It stored about 2,000 bits of data per square inch and had a purchase price of about $10,000 per megabyte.

Few could have guessed in 1955 that the computer industry's first magnetic disk file, the IBM 350 RAMAC (Random Access Method of Accounting and ControI), would one day prove to be of worldwide significance.

Dec 26, 2011 · The RAMAC’s disk storage unit, the IBM 350, weighed over a ton, had to be moved around with forklifts, and was delivered via large cargo airplanes (as above). It stored approximately 5MB of data: five million 8-bit characters on fifty 24-inch-diameter disks, a …

The IBM 350 Disk Storage was a major component of the IBM 305 RAMAC (Random Access Memory Accounting) system, introduced in September 1956. The 350 Disk Storage Unit consisted of the magnetic disk memory unit with its access mechanism, the electronic and pneumatic controls for the access mechanism, and a small air compressor.

The IBM 350 disk drive storage development led to the breakthrough of on-line computer systems by providing the first storage device with random access to large volumes of data.