ELI5: Explain Like I'm 5

Surface (topology)

Okay kiddo, let's talk about surfaces in topology! Imagine you have a bouncy ball. If you look at the outside of the ball, you can see it has a shape or surface. Surfaces are a way to describe how the outside of objects look like.

But some surfaces are a bit tricky to describe because they can have different shapes or properties. These surfaces are important to mathematicians who study topology. Topology is a branch of math that looks at the properties of shapes and spaces, without worrying too much about their exact size or shape.

For example, imagine a coffee cup and a donut. They might look different, but to a topologist, they both have the same surface. This is because they both have one "hole" in the surface. Similarly, a pretzel can also have one "hole" in its surface, even though it looks very different from a donut or a coffee cup.

Topologists use lots of fancy math terms to talk about surfaces, like "manifolds", "homeomorphisms", and "orientable". But the important thing to remember is that surfaces are all about describing the outside of objects in a way that makes sense to mathematicians.