Core-periphery

Okay kiddo, so imagine you have a big group of friends playing together. Some friends are really popular and everyone wants to play with them. Those friends are the "core" of the group. Other friends may not be as popular, and they are the "periphery."

Now let's apply this idea to countries. Some countries are really important and have a lot of power and influence. These countries are the "core" of the world. Other countries might not be as important or powerful, and they are the "periphery."

The core countries often have lots of money and resources, and they're able to kind of control how things work in the world. The periphery countries may not have as much wealth or power, and they might not have as much say in how things are done.

So basically, the idea of "core-periphery" describes the differences between the really important countries in the world (the core) and the less important countries (the periphery).