A government is a group of people that have the power to rule  in a territory, according to the law. This territory may be a country, a state or province within a country, or a region.

Plato listed five kinds of government in The Republic:

The most common type of government in the Western world is called democracy. In democracies, people in a country can vote during elections for representatives or political parties that they prefer. The people in democracies can elect representatives who will sit on legislatures such as the Parliament or Congress. Political parties are organizations of people with similar ideas about how a country or region should be governed. Different political parties have different ideas about how the government should handle different problems. Democracy is the government of the people, by the people and for the people.

However, many countries have forms of democracy which limit freedom of choice by the voters. One of the most common ways is to limit which parties who can for parliament, or limit the parties access to mass media such as television. Another way is to rig the voting system by removing votes from opposition voters and substituting votes for the party in power. Few countries are textbook democracies, and the differences between them has been much studied.[1][2][3]

A monarchy is a government ruled by a king or a queen who inherits their position from their family, which is often called the "royal family." There are two types of monarchies: absolute monarchies and constitutional monarchies. In an absolute monarchy, the ruler has no limits on their wishes or powers. In a constitutional monarchy a ruler's powers are limited by a document called a constitution.

In modern times, monarchies still exist in Great Britain and the Commonwealth, the Netherlands, Spain, Japan, Saudi Arabia, and Thailand, along with several other countries. A monarch may have one of several titles: King or Queen, Emperor or Empress, or Emir.

An aristocracy is a government run by the people of a ruling class, usually people who come from wealthy families, families with a particular set of values, or people who come from a particular place. A person who rules in an aristocracy is an aristocrat. Aristocracy is different from nobility, in that nobility means that one bloodline would rule, an aristocracy would mean that a few or many bloodlines would rule, or that rulers be chosen in a different manner.

Under a dictatorship, the government is run by one person who has all the power over the people in a country. Originally, the Roman Republic made dictators to lead during time of war. The Roman dictators (and Greek tyrants) were not always cruel or unkind, but they did hold on to power all by themselves, rather than sharing power with the people. The Roman dictators only held power for a short period of time.

In modern times, a dictator's rule is not stopped by any laws, constitutions, or other social and political institutions, and can last many years or even decades. After World War II, many governments in Latin America, Asia, and Africa were ruled by dictators. Examples of dictators include Josef Stalin, Adolf Hitler, Augusto Pinochet,  Idi Amin, Muammar al-Qaddafi, and Gamal Abdul Nasser. The rules of these dictators continued from when they took power until when they died, because they would not allow any other person or law to take power from them. There is no evidence of a woman serving as a dictator in modern times.

An oligarchy is a government ruled by a small group of powerful people. These people may spread power equally or not equally. An oligarchy is different from a true democracy because very few people are given the chance to change things. An oligarchy does not have to be hereditary or passed down from father to son. An oligarchy does not have one clear ruler, but several powerful people. Some past examples of oligarchy are the former Union of Soviet Socialist Republics and Apartheid South Africa. A fictional example is the dystopian society of Oceania in the book Nineteen Eighty-Four. Some critics of representative democracy think of the United States as an oligarchy. This view is shared by anarchists.

The simplest idea of government is those who rule over people and land. This may be as small as a community or village or as big as a continent (like Australia and India).

The people who rule can allow others to own land. It is a deed by government that gives this right in the way that laws describe. Some think they have the right to hold land without government permission. This view is called libertarianism. Others think they can do without government. This view is called anarchism.

Almost every place on Earth is connected to one and only one government. Places without government are where people follow traditions instead of government rules, small border disputed areas and the continent of Antarctica, because almost no people live there. For every other place on Earth there is a government that claims 'sovereign control' over it. The word "sovereign" is old and means "control by a King" (sovereign). Governments of villages, cities, counties and other communities are subordinate to the government of the state or province where they exist, and then to that of the country.

It is from Kings and feudalism that modern governments and nation states came. The capital of a country, for instance, is where the King kept his assets. From this we get the modern idea of capital in economics. A government may regulate trade as well as to rule over land.

Governments also control people and decide things about what morality to accept or punish. In  many countries, there are strict rules about sexual intercourse and drugs which are part of law and offenders are punished for disobeying them.

Tax is how government is paid for in most countries. People who buy, sell, import, invest, own a house or land, or earn money are made to pay some of the money to a government.

There are many theories of how to organize government better. These are called theories of civics. Many people think leaders must be elected by some kind of democracy. That way, they can be replaced at election. Many governments are not a democracy but other forms in which only a few people have power.

There are many theories of how to run a government better, and keep people from hurting each other. These theories are part of politics.