The most important invention of the 20th century? To one who was there, it was disk

Computer Technology Review, April, 2004 by Mark Ferelli

The original IBM RAMAC shipped to its first customers in 1956, and the history of magnetic recording changed forever. The first impact was felt in inventory control, where the direct access of the huge drive saved serious money and time. One of the original team at IBM for commercialization of the RAMAC was Bill Donnelly, an IBM staff member and consultant from 1956 to 1998. Bill recently reminisced with editor-in-chief Mark Ferelli.

How did the RAMAC come about?

I went to San Jose in 1956, just prior to the shipment of the first RAMAC. They had built, I believe, nine test models and installed them in different places around the country--like Zellerbach Hall in San Francisco--as test machines. So I wasn't part of the original development of the RAMAC, but I was there from the very beginning, when they started getting serious about building and testing the machines.

How was it received by the original customers?

Very well--or else we would have killed it. It was really unique, because suddenly you had access to what seemed like an enormous amount of information. Five megabytes--five million characters. That would enable a company to keep track of 50,000 inventory items--or something like that. It was a huge step forward. And the unique thing about it was that it had what we first called "random access" and later called "direct access." You could get to any piece of information in less than a second. Prior to that--when they used magnetic tape--if you were searching on magnetic tape the odds were that you would have to search one third of the tape before you could get to any unique piece of information. It was many seconds, even minutes, before you could find something. Then this machine comes along and in half a second you can get to any piece of information. And there were 50,100-character records. So you could keep records of inventory, customers, accounts receivable, and so forth--and it was called the random access machine, RAMAC. And then the spin-masters got hold of it and changed it to the Random Access Method of Accounting Control, and that became the acronym for RAMAC.

When they had already built the development models, I went to see the 305-a RAMAC. I looked at the signals coming off the file and they looked very erratic. My first impression was, "I don't think that this thing will ever work." But I wound up writing the instruction manuals for maintaining and repairing the machines and also taught some of the first classes on it. I knew the machines forwards and backwards, from writing maintenance manuals and teaching people how to keep it running and how to make it run when it didn't.

What was the biggest technical challenge in keeping them up and running?

Just that it was an extremely complex machine. It had every technology that was known at that time. It had core memory, it had the first rotating disk, it had a start program and front board program--it had extremely complex mechanics. It had a card reader and a card-punch, air compressor and a typewriter. So you had to be an extremely gifted person to be able to maintain this machine, because you had to be a mechanic, an engineer, a logician, an early programmer. To me, it was amazing that we could get the machine to run for any period of time, because it had hundreds and hundreds of vacuum tubes, it had relays, it had critical timing measured in milliseconds, and we knew we were onto something really big because it hadn't been done before. And we also knew that if we could get this thing going, it would create a whole new industry. A lot of people call San Jose, "Silicon Valley". But we called it "Iron Oxide Valley" because for a long time we were a bigger part of the economy there than chips.

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Where did the RAMAC go after those initial shipments?

The first one we shipped was to United Airlines in Denver. And it was the first time you could walk into a terminal in Chicago and immediately get an answer to whether you could get a particular seat or not. So we built 1600 RAMACs, which were 5MB apiece. In the personal computer that I'm sitting on right now, I have five times as much capacity as we had built for the entire world at the time. I have a 40-GB drive. We built 8GB for the entire world. I was also one of the historians of disk, because I was there from the very beginning until I retired in '92 and was a consultant until '98. We built 8GBs total for the whole world. Then, the RAMAC could do 30 instructions per second. Today, they measure computer power in millions of instructions per second. The RAMAC--just the disk drive, not the entire system--was $10,000 worth of megabytes. Today it's less than half a cent worth of megabyte. For all of the RAMACs we built for the world in 1956, you would have paid 80 million dollars. Today, you can buy that same disk capacity for four bucks. I base that on a recent ad for Fry's [laughs]. But you can buy a 250-GB drive for $100-$200.

How long did it take for customers to start asking for more capacity?