Generally, computers can only process what they can remember, and the evolution of their means to store information is impressive. From patterns of holes punched in paper cards (1890), to magnetic drums (1932) and later tape (1950), then disks (1971) followed by CDs (1982) and DVDs (1995), and finally the flash cards, mini and micro—all have been at the heart of the progress of Moore’s Law (the prediction of the doubling of transistors every two years). A look back on what has preceded today’s drives, chips, and cards will provide some perspective on the amazing distance covered since the debut of the early computers with their short- and long-term memory problems.




In the beginning, machine memory scale and storage were ridiculous. The first commercial computer with a moving-head hard disk drive was announced on September 14, 1956. The IBM 305 RAMAC had a total of 50 large magnetic disks to serve as secondary storage for the computer. The last of IBM’s vacuum-tube computers, its name, as noted in Wikipedia, “stood for Random Access Method of Accounting and Control, as its design was motivated by the need for real-time accounting in business.”   The 50 24" memory disks were arranged in a column, one above the other, in a case that measured around 1.5 square meters. It occupied 16 square feet of floor space and weighed more than a ton. You might have seen the famous photograph of one of these units being hoisted aloft by a forklift as it was loaded onto a cargo aircraft for delivery to a customer.


The amount of secondary memory storage won by incorporating this hefty cabinet in the RAMAC was impressive for its time. The 50 disks could hold a total of five million alphanumeric characters, which translates to about 5MB. According to a user posting on Digital Photography Review, a 12MP smartphone camera today produces JPEG files that are around 3MB to 9MB in size. So if we took the midpoint of about 6MB, then forget about storing your photos with RAMAC. But, in its time, that 5MB was sufficiently interesting to businesses to command a monthly rental fee of $3,200—around $31,000 in today’s equivalent dollars.


There’s an amusing anecdote about the RAMAC limitations in the Wikipedia history of the computer: “According to Currie Munce, research vice president for Hitachi Global Storage Technologies (which acquired IBM’s storage business), the storage capacity of the drive could have been increased beyond five million characters, but IBM’s marketing department at that time was against a larger capacity drive, because they didn’t know how to sell a product with more storage.”




Today, the machine memory capacities are also ridiculous, but in a different, and wonderfully positive, way.  In June, at the Embedded World 2022 in Nuremberg, Germany, Micron announced its new i400 industrial microSD card designed for edge-storage applications. The tiny card “supports up to 5 years of high-quality, continuous, 24/7 video recording and up to 4 months of storage with the highest capacity microSD card in the world.” The new SD cards are industrial quality according to Micron because their “reliable high quality provides a 2 million hour mean time to failure (MTTF) rating, plus 5-proof protection encompassing water, shock, x-ray, magnet, and impact.” That MTTF translates to 228 calendar years before your card will fail. That’s an impressive number when you think of the longevity expected from your hardware.   Lyle Smith, writing in, explains the nature of the markets for these cards: “The Micron i400 is ideal for fleet dash cameras, smart home security, police body cameras, and AI-enabled cameras in factories—all need storage capable of handling media-rich data. Moreover, because of its massive capacity, the new i400 is also ideal for video storage at the edge and hybrid VSaaS deployments [video surveillance as a service]."   When you think of the progress made from the IBM 5MB stack of platters to the Micron microSD, the contrast is stark. In the recent past, there was a cabinet weighing a ton, that cost $30,000 a month, that might store a couple of snapshots for you, and now we have a small (0.56" 5 0.43" 5 0.039") wafer that can balance almost unnoticed on the tip of your finger, will probably cost $300 to $400, and can save around 250,000 photos securely for the next two centuries to come. It’s the kind of progress we haven’t seen in previous revolutions.


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