I love prototype technology. There's a magic in seeing what the original working model looked like, which makes so many systems instantly more-understandable to a lay person. Strip away the perfection and packaging, and you can see what's really going on.

In this video, Bill Hammack—professor of engineering at the University of Illinois at Urbana-Champaign and part-time Engineer Guy for the Internet—demonstrates this effect by introducing us to a model of the world's first transistor. An amplifier for electric signals, transistors were at the heart of all the miniaturization and techno-populism that began in the 1960s and 70s. Watch this video, and you'll understand how a transistor works, and why these little things are so very important. Thanks, Engineer Guy!

Learn more at PBS's great Transistorized! site