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Bill Healy, executive vice president at Hitachi, holds up a platter from a 1-inch microdrive in his right hand. In his left is a 24-inch platter from IBM’s RAMAC (Random Access Method of Accounting and Control), which came out 50 years ago. A 1-inch 8GB platter holds more than 80,000 times as much data as a single 24-inch RAMAC platter. An 8GB 1-inch drive holds 1,600 times as much data as RAMAC.
A 14-inch platter (right) is dwarfed by its 24-inch predecessor. Fourteen-inchers came out in the early 1960s, when demand began to grow. Disks with 14-inch platters were stacked into heavy, but moveable, bundles that could be carried from one system to another.
In 1952, a small IBM research laboratory for finding new approaches to data processing was founded in a leased building in San Jose, Calif., under the leadership of Rey Johnson. Under Johnson’s leadership, the lab created the first magnetic disk drive and an associated online transaction-oriented system.
This model established the feasibility of a rotating magnetic disk stack. A vertical shaft was chosen later to simplify the addition of other access mechanisms.
The original hard disk drive, known as the RAMAC, in 1956 stored only 5 megabytes of data on 50 disks, 24 inches in diameter. It weighed more than 250 kilograms.
Healy of Hitachi shows off one of the original RAMAC systems. Technically, the RAMAC is the entire storage system, and the drive inside of it is called the 350. Crown Zellerbach, a San Francisco paper company that produced computer card stock for IBM, got the first RAMAC. Customers always wanted to see it, said Jim Porter, president of Disk/Trend, who worked at Crown at the time.rn
rn”It made a fair amount of noise because there was forced air that blew out between the head and the disk to keep the head from rubbing on the disk,” Porter recalled in an interview last month. “It was the air compressor that made the noise.”
The RAMAC’s 50 stacked platters could have held just about two iTunes songs.
Compare the size of the RAMAC’s disk stack with a modern 1-inch microdrive platter. In the RAMAC, the head couldn’t touch the platters. Engineers had to compensate for air, dust and other environmental factors. Later drives encapsulated the head inside the drive.
The RAMAC’s head scooted up and down the stack to find data. There were 100 stops–one for each side of the 50 magnetic platters.
On the left is an aerial photograph of IBM’s hard drive plant in Silicon Valley in the 1970s. On the right is the same site 20 years later.
John Haanstra, left, initiated a study of the system implications of large-scale random access. His work changed the course of the computer industry. rn
rnOn the right is the world’s first data-processing system for storing computer data on magnetic disks. The system enabled the handling of transactions as they occurred. This demonstrated the path to the online, real-time applications that are so prevalent today.
This 1957 prototype demonstrated a new technology using disk drive heads and tracks rather than magnetic tape. The first commercial use of the technology was IBM’s 3330, in 1971.