The ruling class is a group of people who have a lot of power and control over others. Think of them like the big kids in school who always get to make the rules and tell everyone else what to do.
In society, the ruling class can be made up of people who have a lot of money, like rich business owners, or people who hold important positions in the government, like elected officials or judges.
The ruling class often use their power to make decisions that affect everyone else, like passing laws or deciding how tax money is spent.
Many people think that the ruling class can sometimes abuse their power and only think about their own interests instead of what's best for everyone. This can be like the big kids at school who always get their way and don't consider how it affects the other kids.