ELI5: Explain Like I'm 5

Perfectly normal Hausdorff space

Imagine you have a special type of space called a "perfectly normal Hausdorff space." It's like a room that's extra special because you can do certain things in it that you can't do in other rooms.

First, let's talk about what it means to be "normal." In a normal space, if you have two separate points in the room, you can draw a line between them without touching any other points. It's kind of like if you take two toys in your room and draw a line between them without touching any other toys.

Now, let's talk about being "Hausdorff." That means if you have two separate points in the room, you can draw two separate lines (one for each point) without touching each other. Basically, you can draw two non-overlapping lines in the room.

When you put these two ideas together, you have a perfectly normal Hausdorff space. It's a space where you can draw lines between any two points and those lines won't touch any other points.

So why is this important? Well, it makes the space really nice to work with because you have a lot of flexibility to move things around without running into other things. It's like having a big empty room where you can put whatever you want without it bumping into anything else. And mathematicians really like nice spaces like this because they make it easier to prove things and understand how things work.