My proverbial file drawer is bursting with revolutions to write about: artificial intelligence, thought-driven cars, and genetic monsters, to name a few.  But where to begin?  It seems inauspicious to inaugurate this blog with a downer like climate change, and as much as I’d like to lead off with an article about monkeys in space, I felt it lacked the necessary gravity.

In the end, I chose a subject a little closer to home: today’s featured revolution is in the field of data storage, and our special guest is the megabyte, a unit of storage capacity.

I may have just scared off half my potential readers right there!  Look, I know “data” sounds a lot less exciting than all those other topics I was considering (and don’t worry, I’ll get to the genetic monsters one of these days).  But spend a few paragraphs witnessing the megabyte’s storied birth, its spectacular upcoming death, and the weirdness of the world afterwards, and I’ll think you’ll agree with me that it’s quite a trip.

The Megabyte’s family album

Also pictured: one of the earliest computers

The megabyte, being an abstract unit of measurement, doesn’t really have an exact birthday, but this is as good a place to start as any.  Any computer science historians in the house?  That’s okay, I’m not either, I had to get the picture from Wikipedia.  Those metal crates are RAMAC-350s, brought to you by computer giant IBM.  They’re one of the very first hard drives ever made, back in 1957, and they weigh a ton (literally).  Just two things to remember: they each cost $1.3 million (in inflation-adjusted modern dollars) and could hold 5 megabytes.

You remember these... don't you?

This one you probably recognize, unless you’re well below the legal drinking age.  Cassette tapes were the music format of choice for two decades, bridging the CD with the vinyl record.  Say you bought a copy of Escape when it came out in 1981, and the rest of Journey’s oeuvre up to that point (this is all purely hypothetical, of course.  I would never do such a thing).  That would have run you about $150 (modern) dollars, and provided you with several hours of static-laced commercial rock music – the equivalent of 11 megabytes.

Finally, if you’ve ever taken apart an old computer, you’ll recognize this as a basic hard drive, such as you might find in a typical generic email machine.  You can get a 1-terabyte hard drive (that’s 1,000,000 megabytes) on the internet right this minute for about fifty bucks, and maybe even free shipping if you shop around.

Do the math

A few quick back-of-the-napkin calculations will clarify the megabyte’s ultimate destiny.  It’s 1957, the cold war is brewing, and a megabyte of storage costs a cool quarter mil – $280,000.  Flash forward a quarter century.  ET’s up for an Oscar, the cold war is still brewing, and the same megabyte runs you thirteen bucks and change.  And today, another 25 years on, that megabyte will dent your bank account to the tune of 5/1000 of a penny.

This trend qualifies as exponential.  Computer scientist and data storage pioneer Mark Kryder has recently suggested that storage density is doubling every year (I’ve generally been referring to lower costs, but higher density is roughly equivalent).  Here’s a visual representation – note that the Y-scale is logarithmic.

courtesy wikimedia commons

This is an extremely rapid rate of change.  Of course we can’t state with any certainty that the trend will continue forever, and the usual caveats apply.  For one thing, there are plenty of non-trivial technological obstacles, and it’s possible there’s even be a theoretical ceiling.  But if innovation continues to outpace its obstacles as it has for 50 years, and if there’s no upper limit to how much storage space we could hypothetically produce, then we’ll eventually have a world where digital storage is so cheap and plentiful that it’s effectively infinite.  Stay tuned for part 2, where we’ll take a peek at what that world might look like.  Hint: it contains both biblical allusions and science-fiction references.

Oh, and about the title of the post.  As an incidental consequence of having infinity of anything, the relevant units of measurement become completely obsolete.   Alas, poor megabyte!  I knew him, Horatio.