What are the different forms of state (unitary, federation, and confederation)?

A government consists of a set of legal and political institutions that control relationships between society and outsiders and the relationships among the members of the society. There are various systems of government, including confederation, federation, and unitary.
In a unitary system, the federal government performs all government functions. The federal government carries out police powers, taxation, and lawmaking responsibilities. Subnational national units are responsible for matters within their jurisdiction. However, the power of these units comes from the federal government. Many countries have a unitary system of government. In some instances, the regional units of government have a good deal of power and authority. This is true in Great Britain, where Northern Ireland, Scotland, and Wales have a good deal of autonomy. In France, the federal government has strict control over the regional units of government.
In a confederation, the federal government has limited power. The states have a great deal of power. Only powers that are needed for continuing the confederation are given to the federal government. The states make their own laws and levy their own taxes. In the United States, the first plan of government was a confederation. It was called the Articles of Confederation. The federal government had very little power, which eventually led to problems and to the writing of a new plan of government. No modern nations have a confederation form of government. However, the British Commonwealth of Nations and the North Atlantic Treaty Organization have aspects of confederation principles.
In a federation, there is a strong federal government. The states also have a good deal of power. The United States is an example of a federation. The federal government has more power than the state governments, but the state governments have a good deal of power and authority. Local units of government, such as cities, towns, and villages, also exist within this system. The local forms of government also have significant powers within their areas of jurisdiction. In the United States, both the state and the federal government share some powers, such as taxation. However, some powers are given only to the federal government, such as the power to declare war. There are also some powers set aside only for the state governments, such as the power to determine educational policies within that state. However, no state law can contradict a federal law, and the states must follow the federal laws. The same is true for the local government units.
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