Organic law

An organic law is a law, or system of laws, that form the foundation of a government, corporation or any other organization's body of rules. A constitution is a particular form of organic law for a sovereign state.
By country.
France.
Under Article 46 of the Constitution of France, organic laws (in French, "lois organiques"; in English sometimes translated as Institutional Acts) are a short, fixed list of statutes (in 2005, there were about 30 of them) specified in the Constitution. They have constitutional force and so overrule ordinary statutes. They must be properly enacted by the Parliament of France and must be approved for constitutionality by the Constitutional Council of France before they can be promulgated.
Organic laws allow flexibility if needed. An important category of organic laws includes the budgets of the French state and French social security. Other organic laws give the practical procedures for various elections. Organic laws reduce the need for amendments to the constitution.
Spain.
Under the current Spanish Constitution of 1978, an Organic Law has an intermediate status between that of an ordinary law and of the constitution itself. It must be passed by an absolute majority of the Congress of Deputies. The Spanish Constitution specifies that some areas of law must be regulated by this procedure, such as the laws developing fundamental rights and freedoms recognized in the first section of Chapter Two of Title I of the Constitution, as well as the laws that approve the Statutes of Autonomy of the autonomous communities of Spain, among others. Prior to the 1978 constitution, the concept did not exist in Spain, but it is inspired by the similar concept in the 1958 French Constitution.
United States.
The organic laws of the United States of America can be found in Volume One of the United States Code which contains the general and permanent laws of the United States. U.S. Code (2007) defines the organic laws of the United States of America to include the Declaration of Independence of July 4, 1776, the Articles of Confederation of November 15, 1777, the Northwest Ordinance of July 13, 1787, and the Constitution of September 17, 1787.