what is the main feature of a federation
Federation A federation (also known as a federal state) is a political entity characterized by a union of partially self-governing states or regions under a central (federal) government. In a federation, the self-governing status of the component states, as well as the division of power between them and the central government, is typically constitutionally entrenched and may not be altered by a unilateral decision of either party, the states or the federal political body. Alternatively, federation is a form of government in which sovereign power is formally divided between a central authority and a number of constituent regions so that each region retains some degree of control over its internal affairs.[1][2]
Federal government of Mexico The federal government, known as the Supreme Power of the Federation, is constituted by the Powers of the Union: the legislative, the executive, and the judicial. Mexico City, as the capital of the federation is the Federal District, the seat of the powers of the Union. All branches of government are independent; no two separate branches must be vested upon a single person or institution, and the legislative power must not be vested upon a single individual.