A tax is involuntary fees paid by individuals or companies in a state, or the functional equivalents of a state, including tribes, movements of secessionist or movements revolutionary. Taxes can be paid cash or in kind or like work of corvee. The modern systems of imposition of capitalist, whose the most effective circulation commodified goods and services are conceived to encourage, are taken cash. In kind and corvee the imposition are characteristic of the traditional states or functional pre-capitalist and their equivalents.

The means of the imposition, and the uses to which the funds increased by the imposition should be put, are a question of hot conflict in the policy and economic sciences, thus of the discussions of the imposition are frequently tendentious. The finance public are the field of science and political economic sciences which treat the imposition.