Close your eyes and just listen. A bird outside, a door closing, someone laughing, your own breathing. Sounds are everywhere — but where do they all come from?

Here is the big secret, and it is true for every single sound you have ever heard: a sound is made by something vibrating. To vibrate means to wobble to-and-fro really fast, back and forth, back and forth. That tiny wobble bumps the air and travels all the way to your ears — and that is what you hear.

Try it on a drum. When the drum is resting the skin is flat and still — no sound. Give it a Hit and the skin wobbles up and down really fast. That wobbling is the sound being born. Watch the skin: still means quiet, wobbling means boom!

You can feel this yourself. Rest your fingers gently on your throat and hum a tune — you will feel it buzzing! That buzz is your voice box vibrating. Touch a guitar string right after it is plucked and you will feel it shivering too. No wobble, no sound.

Your sound adventures

First discover how every sound is born in Making Sounds. Then find out what makes a sound high or low, loud or quiet, in Pitch and Volume, and how a wobble races across a room to reach you in How Sound Travels.