There was a professor at Penn that would keep a light bulb on his shelf. He took it out once and asked us what it is: none of us could answer it. It turns out,

There was a professor at Penn that would keep a light bulb on his shelf. He took it out once and asked us what it is: none of us could answer it. It turns out, it was a bit from the Eniac! The lightbulb is connected to a magnet so that when switched on, the magnet would represent and 1, and the lightbulb would light up alerting the programmers that the bit is indeed on. There would be 16 (or 32 I can't remember) such bits on a wooden board, representing one integer. It's wild how far we have come. At the computer lab in the school, there is a part of the ENIAC on display, it was huge.