Social hierarchy is a way of organizing people based on their importance in the group, or how much power they have. It's like a pyramid, where the most important or powerful people are at the top, and the least important (or most powerless) people are at the bottom. So, in a social hierarchy, the people at the top have the most power and make all the decisions, while the people at the bottom have very little power and must follow instructions from the people at the top.