The Evolution of Hard Drives and the Four Laws that govern this...

Pingdom a site that presents data about technology did an interesting post on the evolution of hard drives. I am constantly amazed about the rapid rise in hard disk capacity. The photo at the right is one of an early IBM hard drive array which held five megabytes of information. Now it is easy to purchase a terabyte drive (1012 trillion bytes of information) for under $500 that will fit in a brief case.
The graphic compares both size and capacity of hard disks 30 years apart. In 1980 the computer store that I used went out of business and they had a sale on hard drives for $1 per megabyte. I bought 10 of those drives for $200 - linked them together and had what I thought would be reasonable storage capacity for my office for a long time. When I bought my first computer only a couple of years before the thing used 5 1/4" floppies which I think were in the range of $200 per box - those disks were in the range of 5 kilo bits (1 kilobit = 0.0001220703125 megabyte or 1.16415321826935e-10 terabyte).

Put another way, when I started on email the university that I had my account on had a network storage capacity that was less than one third of the total capacity in my home network. All those bits and bytes are really not important (and increasingly so) but they portend the ubiquity of information of all types. The economic lessons here are more important than the technological one. First as Moore's Law (the processing power of a microchip doubles every 18 months; corollary, computers become faster and the price of a given level of computing power halves every 18 months) and Gilder's law (the total bandwidth of communication systems triples every twelve months) and Metcalf's law (the value of a network is proportional to the square of the number of nodes; so, as a network grows, the value of being connected to it grows exponentially, while the cost per user remains the same or even reduces) continue to operate a new law comes into play. That is Linder's law. Stephan Linder was a Swedish economist who argued in the early 1980s that as wealth increased (and his idea could be extended to the wealth of information) the value of time increased. Thus, the rationing method does not become dollars but time.