A monarchy is a form of government in which a single person, the monarch, is head of state. The monarch may be a king, queen, emperor, or empress. Monarchies can be hereditary, in which the monarch is succeeded by a member of their family, or elective, in which the monarch is chosen by a group of electors.
Republic
A republic is a form of government in which the head of state is elected by the people. Republics can be presidential, in which the president is both head of state and head of government, or parliamentary, in which the prime minister is head of government and the president is a ceremonial figurehead.
Dictatorship
A dictatorship is a form of government in which a single person, the dictator, has absolute power. Dictatorships can be military, in which the dictator is a military officer, or civilian, in which the dictator is a civilian.
Oligarchy
An oligarchy is a form of government in which a small group of people have power. Oligarchies can be hereditary, in which power is passed down from one generation to the next, or elective, in which the oligarchs are chosen by a group of electors.
Democracy
A democracy is a form of government in which the people have the power. Democracies can be direct, in which the people make decisions directly, or representative, in which the people elect representatives to make decisions on their behalf.
Theocracy
A theocracy is a form of government in which the state is governed by religious law. Theocracies can be monarchies, republics, or dictatorships.