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The first random-access disk drive revolutionized how businesses use computers and set the stage for everything from space flight to e-commerce
Men looking at a printout in front of the IBM 305 RAMAC, the first computer to use a random-access disk drive. A woman is seated at an IBM 380 console desk attached to the IBM 370 printer.

In 1952, IBM dispatched a band of engineers to a new lab overlooking a plum orchard in a swath of California yet to be coined Silicon Valley. Their mission was to scrutinize how computers accessed data, an arduous process that at the time involved running a stack of hole-punched cards through a machine and shuffling through the data.

After four years of trial and error, the team revealed a complete overhaul of status quo computer memory systems. The IBM 305 RAMAC — or simply RAMAC — was the first computer to use a random-access disk drive. The progenitor of all hard disk drives created since, it made it possible for any computer user to quickly and easily store, access, alter and erase data without technical training or manual intervention. It paved the way for the invention of the relational database, empowered businesses to think about data in new ways, and ultimately laid the groundwork for everything from spaceflight and ATMs to search engines and e-commerce.

Before RAMAC, information retrieval through a computer took hours or even days. RAMAC could access and manipulate data exponentially faster — in seconds. The machine took up the better part of a room and stored a paltry amount by today’s standards — a mere 5 megabytes — and yet it represented a massive leap in speed and efficiency that made the relational database possible and changed how businesses collected, used and applied information. At the time, the company described RAMAC’s underlying process as “miracle memory.”

Hacking a novel solution
Overcoming technical, design and material challenges

The notion of random-access memory wasn’t new, but every previous attempt was too slow to be practical. Under the guidance of Reynold B. Johnson, who would go on to become an IBM Fellow, team members hacked their way to a novel solution. The team tried rods, strips, tapes and flat plates before settling on an approach that involved magnetizing aluminum disks by coating them with iron oxide paint. Magnetic spots on each disk represented characters of data, and a magnetic arm — akin to a record-player needle — would read the spots as the disks rotated at blinding speed. 

Getting the system to work required overcoming a number of technical, design and material challenges. The disks needed to be strong, absolutely flat, and light enough to be rotated by a motor. In the first trials, the disks warped at high speeds. Researchers responded by gluing two disks together. Unlike an actual record player needle, the magnetic arm couldn’t physically touch the disk, lest it destroy data. So researchers created a version that blasted out compressed air to keep the contraption hovering above the disk. Then came the issue of capacity. A single disk could not store enough data to be useful. So the team stacked 16 disks horizontally — disbelieving IBM executives referred to the unlikely design as the “baloney slicer.”

The final hurdle involved finding a way for the arm to reach the right place on the right disk instantly. “That was our goal: to go from any track, which was 6 inches in on a disk, out, down 2 feet to the bottom, and in 6 inches — in half a second,” Johnson recalled of the challenge. “We achieved something like 800 milliseconds, and that’s where the product came out.” 

The resulting storage system could hold 5 million binary decimal encoded characters at 7 bits per character. The ultimate apparatus was the size of two kitchen refrigerators, weighed more than a ton, and stored 5 to 10 megabytes of data — the rough equivalent of a few of today’s MP3 files.

The name RAMAC was conceived by the researchers as an amalgam of “random-access memory” and the “AC” suffix of the UNIVAC computer, which was popular at the time. Marketers later altered the suffix to stand for “accounting and control" since demand for the unit initially stemmed from the need for real-time accounting in commerce. RAMAC immediately addressed the paralyzing overload of analog data in the enterprise, making it possible to access the data equivalent of 64,000 punched cards almost instantaneously.

  
RAMAC made it possible to access the data equivalent of 64,000 punched cards almost instantaneously
 
RAMAC impact
From global businesses to the World’s Fair

Orders began pouring in. Early customers included 3M, New York University, Norfolk Naval Shipyard, Pfizer and United Airlines, among others. Within two years, RAMAC had been deployed by the United States Custom House to monitor Atlantic Ocean traffic, reducing the response time to ship distress calls to five minutes.

In 1958, RAMAC was demonstrated in the US pavilion at the Brussels World’s Fair. During the 1960 Olympic Games in Squaw Valley, California, 36 IBM employees staffed a center that provided electronic data processing systems for scoring. Previously, all scoring calculations had been done manually and could take hours to complete. RAMAC did the job in minutes.

The microprocessor is rightly hailed as the linchpin of modern computing; without the invention of RAMAC, our world would look much different today. In addition to speeding access to information, RAMAC rendered valuable enterprise data less vulnerable to theft and destruction, and caused computation costs to plummet.

RAMAC eventually gave way to a raft of new data storage technologies that were faster, cheaper and took up less space,  while holding much more information. According to Computerworld, 1 terabyte of data storage in the 1950s would have cost USD 1 trillion. Today it can be had for less than USD 50 and fit in your pocket.

By those standards, RAMAC may seem quaint, and yet the technological breakthroughs made by Johnson and his team unquestionably broke new ground and set the world on a new path. RAMAC radically altered how organizations could organize, conceptualize and gain insight from their data and spawned the era of real-time information retrieval, which we all take for granted in everyday life.

USD 1 Trillion

Price of 1 terabyte of data storage in the 1950s

USD 50 

Price of storing 1 terabyte of data today

 

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