Really, Really Big Numbers (Revisited)

In the absence of our long-lost (and very much missed) fellow blogger Numeric Life, I've written about big numbers several times - you can read two of my past posts about really big numbers here and here. I got to thinking about really big numbers again a few days ago when I read this interesting article in the Washington Post: Exabytes: Documenting the 'Digital Age' and Huge Growth in Computing Capacity.

The point of the article is that we have reached the point at which there is so much data being stored in so many forms and places that we have had to invent a new term for amounts of information - the exabyte. The exabyte is defined as one billion gigabytes ... which, in turn, is defined as a thousand megabytes ... and a megabyte is, of course, a million bytes.

That's a lot of bytes.

I often think about the first computer Agnes and I bought, back in 1988 or so. It was a Cordata AT with the MS-DOS operating system and a staggeringly huge hard drive - 20 megabytes. I distinctly remember telling Agnes that I could hardly imagine so much storage - "We'll never fill it up," I said.

Well, I've been wrong once or twice ... Today, that hard drive would have held about 10 of the digital photographs I take of my grandchildren.

I recently replaced the 500 gigabyte hard drive in my iMac with a new Western Digital Green drive - one terabyte.

For someone as bad with numbers as I am, these are some pretty dauntingly large figures. The Washington Post article linked above contained this very interesting diagram to illustrate the explosive growth in stored information:

If the graphic is too small to read, you can see it in full size here.

So, how do we visualize such vast numbers? The graphic above is good, but it's two-dimensional ... how do we put it into everyday imagery? According to the study conducted at the University of Southern California in 2007 on which that graphic was based, the total world-wide capacity to store information digitally on media of all types was 276 exabytes. To put it in more visually friendly terms, picture in your feeble mind a tower of compact disks, each one representing one digital music album. To hold 276 exabytes, that tower would start at the surface of your table and top out 50,000 miles beyond the orbit of the moon.

That's pretty impressive. Of course, unfortunately, not all data is created equal, or is of equal value. I imagine that a pretty big chunk of that data consists of spam, digital pornography, violent religious bigotry, and other such digital sewage.

Too bad we don't have a better way to store that stuff. Perhaps we need a new term to measure it ... like the flushabyte, megacrap, or gigascum.

We can only dream. And hope that Numeric Life comes back to help us make sense of it all.

Have a good day. Flush some of that old data. More thoughts tomorrow.

Bilbo