International political economy is like when you and your friend trade snacks at lunch, but on a really big scale with countries around the world.
Sometimes countries have different things that they are really good at making, like toys, clothes or electronics. They make so many of those things that they have extra to sell. Other countries might not be as good at making those things, but they might be really good at making something else that the first country doesn't have as much of, like food or oil.
So, the countries start to trade with each other. The first country sends some of their toys to the second country, and the second country sends some of their food to the first country. This makes everyone happy because they get things that they need or want.
But, this trading can also cause problems. Sometimes, one country might not play fair and give the other country a bad deal. Or one country might be so good at making something that it pushes other countries out of business. Sometimes countries might even get mad at each other and stop trading altogether.
So, people who study international political economy try to figure out ways to help countries trade in a fair and peaceful way. They look at things like politics, laws, and economics to understand how countries can work together to make everyone better off.