Democracy is a system of government where citizens participate in political decision making through voting. There are various types of democracies including representative democracy, where citizens vote for representatives, and direct democracy, where citizens vote on policy initiatives directly. Representative democracies can take the form of parliamentary or presidential systems. Hybrid systems combine elements of direct and representative democracy, using mechanisms like referendums. For a democracy to be effective, it must protect citizens' rights and have separation of powers to prevent any one branch from accumulating too much authority.