Happy Birthday, Little Guy!

Today is the sixtieth birthday of perhaps the most important character of the twentieth century. Number twenty was a pretty momentous century, what with two world wars, space travel, relativity, quantum mechanics, and the atomic bomb, but I think that the little guy was probably the star nonetheless. I'm talking, of course, about this guy.

The transistor was invented by scientists William Shockley, John Bardeen and Walter Brattain to amplify voices in telephones for a Bell Labs project, an effort for which they later shared the Nobel Prize in physics.

On Dec. 16, 1947, Bardeen and Brattain created the first transistor. The next month, on Jan. 23, 1948, Shockley, a member of the same research group, invented another type, which went on to become the preferred transistor because it was easier to manufacture

The subsequent invention of the integrated circuit allowed an ever increasing number of transitors to be crowded onto a chip of silicon, with the current record about a billion. I said ever increasing, but everyone knows that exponential growth can't continue forever. The finite size of the atom, and the nature of solids made of atoms, set a minimum size on transitors, and current technology is approaching that limit.

Moore's 'law' famously predicted that the number of transitors on a chip would double every 18 to 24 months, and that law has held now through almost thirty such doublings. Most industry people think that there are a few more left, perhaps as many as four or six, but almost certainly not as many as ten.

This still leaves the transistor count of this ultimate chip an order of magnitude or so short of the neuron count in a human brain. However, transistor switching speed is roughly a million times faster than a neuron's, so why aren't computers a lot smarter - like a hundred thousand times smarter - than us? There are a few possible answers:

• They are, at some things, like arithmetic, sorting, and searching
• Their programs are less efficient
• Information is stored not in neurons, but in their connections, and we have trillions of those

Transistors are now virtually everywhere in our technologies, including the modern versions of those technologies that predate it, like the car, plane, and television, as well as more modern things like the PC, cell phone, and IPOD.

So: Happy Birthday, Little Guy! Keep on shrinking.