Checks and balances is a system used in government to ensure that no single branch becomes too powerful. It divides authority among three branches: the executive, legislative, and judicial. Each branch has specific powers and responsibilities, allowing them to monitor and limit each other's actions. For example, the legislative branch can create laws, but the executive branch has the power to veto them. Meanwhile, the judicial branch can review laws to determine if they are constitutional. This system promotes accountability and helps protect the rights of citizens by preventing any one branch from dominating the government.