What are fourier transforms?

A Fourier Transform is like turning a song into a list of its building blocks, the notes that make it up.

Imagine you have a toy drum set. When you play a beat, it sounds like one big, exciting rhythm. But if you could take apart that beat and see all the individual drums hitting at different times, you’d understand how it was made. The Fourier Transform does something similar with sound, or any wave-like thing, by showing you all the simple parts (like different drum hits) that make up the whole.

Think of a melody on a recorder. It’s one smooth tune, but if you could see it as a bunch of little notes playing at different speeds and volumes, you'd have a Fourier Transform of that song.

It's like looking at a jigsaw puzzle, from far away, it just looks like a picture. But when you get up close, you can see all the separate pieces, each one a part of the whole.

If you've ever watched ripples in a pond after a stone is thrown in, those waves are like sound waves. A Fourier Transform would be like taking a photo of all the different ripple sizes and how fast they're moving, it helps you understand what made that pattern.