Whitehead double

So imagine you have a little ball in your hand. Now imagine that ball is actually two balls stuck together. That's kind of like a whitehead double!

A whitehead double happens in math when you take a shape (like a curve, which is just a wiggly line) and "double" it. But instead of just making a copy of it, you change the way it's oriented. That means you mirror the shape and then stick them together at certain points.

It's kind of like looking in a mirror and seeing your reflection. You and your reflection are the same shape, but you're facing opposite directions.

Mathematicians study whitehead doubles because they can tell us interesting things about shapes and spaces. But for now, just remember that a whitehead double is like having two balls stuck together, except in math!