ELI5: Explain Like I'm 5

Peano curve

Okay kiddo, imagine you have a piece of paper and a pencil. If you draw a straight line on the paper, it goes from one point to another without any turns or curves. But what if you wanted to draw a line that goes all over the paper without lifting up the pencil? That's where the Peano curve comes in.

The Peano curve is a way of drawing a line that covers every point in a square. It was first thought up by a guy named Giuseppe Peano, which is why it's named after him.

To draw a Peano curve, you start with a square. Then you divide that square into nine smaller squares, like a tic-tac-toe board. Then you draw a line that touches every single one of those little squares, without lifting up your pencil.

But wait, that's not all! Next, you divide each of those nine little squares into nine even tinier squares. That gives you a total of 81 tiny squares. And once again, you draw a line that touches every single one of those 81 little squares, without lifting up your pencil.

You keep doing that over and over, dividing the squares into smaller and smaller pieces, and drawing a line that passes through every single one of them. At the end of the process, you'll have drawn a line that covers the entire square.

It's kind of like a maze, where you're trying to find a way to get from one end to the other while touching every single part of the maze. The Peano curve just does it in a really cool and efficient way.

So to sum it up, the Peano curve is a way of drawing a line that covers every point in a square, by dividing the square into smaller and smaller squares and drawing a line that touches every single one of them. And once you've drawn the line, you'll have covered every single point in the square. Pretty cool, huh?