ELI5: Explain Like I'm 5

Locally compact space

Okay kiddo, imagine you have a big toy castle that you can play in. Every room in the castle has an imaginary boundary where you can't go outside of it, like a drawn line on the floor.

Now, let's say you have a toy car that you want to drive around the castle. You can go into some rooms with the car, but for others, the car is too big and cannot fit inside. So, you need to park the car outside the room before you can go in.

A locally compact space is like your toy castle. It's a place where you can walk around and explore, but some parts of it are more compact than others.

More specifically, in a locally compact space, you can have rooms that are like the ones in your castle where you can't go outside of them, but everywhere else there is enough room to move around.

So, imagine a space like a city block where almost everywhere you can walk freely, but there might be small alleyways or narrow paths where you can't go, and those areas are considered compact.

Overall, a locally compact space is a place with some tight spaces, but mostly plenty of room to move around.