ELI5: Explain Like I'm 5

Fréchet–Urysohn space

Imagine you have a bunch of different shapes like circles, squares, and triangles. Now imagine you want to put them all in a room in such a way that no two shapes touch each other. This would be really hard to do, right?

Now imagine you have an even bigger collection of shapes – not just circles, squares, and triangles, but all kinds of weird and wacky shapes. You might think it would be impossible to put them all in a room without any two shapes touching.

But actually, there is a special kind of space in math called a Fréchet–Urysohn space that makes this possible. In a Fréchet–Urysohn space, you can put any number of shapes in the room without any two of them touching.

This is really important in math because it helps us understand how different shapes and spaces are related to each other. It also has applications in places like computer science, where we might need to store a lot of different pieces of information without any of them overlapping.