Fiscal systems gather all the taxes and contributions levied to fund the State. These taxes and contributions share the characteristics of being compulsory and unrequited payments to the government, in the OECD sense. Historically, fiscal systems have shown their scalable nature as they are embedded in larger economic, social, political, and cultural systems. It is possible to distinguish the positive analysis and the normative analysis of fiscal systems. The positive analysis enlightens fiscal systems characteristics in terms of tax structure, while the normative analysis questions the qualities of a good tax system.