Grace Hopper Explains a Nanosecond

In this short clip from 1983, legendary computer scientist Grace Hopper uses a short length of wire to explain what a nanosecond is.

Now what I wanted when I asked for a nanosecond was: I wanted a piece of wire which would represent the maximum

distance that electricity could travel in a billionth of a second. Now of course it wouldn’t really be through wire — it’d be out in space, the velocity of light. So if we start with a velocity of light and use your friendly computer, you’ll discover that a nanosecond is 11.8 inches long, the maximum limiting distance that electricity can travel in a billionth of a second.

You can watch the entirety of a similar lecture Hopper gave at MIT in 1985, in which she “practically invents computer science at the chalkboard”. (via tmn)

• computing
• Grace Hopper
• science
• time
• video