Physics
Oscillators
Quick fact
The most accurate oscillator in the world is an atomic clock, which uses the oscillation of cesium atoms to keep time to within one second over millions of years.
Why this is interesting
You've seen a pendulum swing, a guitar string vibrate, and a heart beat – what do they have in common? They are all oscillators, systems that move back and forth around a central point, and their rhythm is the secret behind everything from timekeeping to wireless communication.