In government, adults make the rules we live by and then make sure that those rules are followed. They also make sure that we get the services we need. These services can be things like public education, fire departments, police, and the postal service. Government also provides security and stability, as well as food, housing, and health care for the poor.

Governments are also responsible for managing externalities and social inequality, and for promoting economic growth. But, because most problems only appear after they occur, governments often find it difficult to act in advance.

The oldest and simplest justification for government is to protect citizens from violence, both from each other and from outside threats. This function is illustrated by Thomas Hobbes’ Leviathan, in which the horrors of life without a government are depicted as unrelenting chaos and uncontrollable violence. Governments guard against these horrors with armed forces, intelligence operations, and laws that punish or expel spies and terrorists and prohibit the export of materials that can be used in attacks on a country.

Another key justification is to provide public goods, that is, services that cannot be provided privately. For example, the fire department doesn’t demand payment before it puts out a fire or the police don’t charge people for protecting them. Governments also provide other public goods such as public education, roads and bridges, mail service, and water and air pollution control.

In most modern democracies, people elect a group of people from each community to represent them. These representatives are known as a legislature or parliament. The United States, for example, has a House of Representatives and Senate. The Senate has 100 members, with two senators per state. The House of Representatives has 435 members, with a number of additional voters depending on the size of the state.

The people’s elected representatives then try to secure funding to support the services they need for their constituents. For example, state governments might allocate money for the operation of state universities and the maintenance of highways. National governments might spend money on defense, Social Security, and the preservation of national parks.

The government must also deal with problems that are not of its own making, such as terrorism or climate change. In these cases, it can work with other countries to prevent or resolve them. The United States, for example, has diplomats who communicate with the leaders of other countries and try to make deals or solve problems. The President of the United States is a part of this team, and he represents all the American people when he talks with the leaders of other countries.