The constitution is the highest law of the country. It reflects the objectives of the state and the rights and aspiration of its citizens. It establishes the rule of law and sets limits on government authority. A constitution is a living document that indicates the way in which a country is governed. The primary function of the constitution is to lay out the basic structure of the government according to which the people are to be governed. 

A constitution has three distinct but interrelated components. 

• Set of Rules – A constitution is a set of rules that describes the structure, powers and functions of the three organs of government to ensure that each organ functions without its jurisdiction. It lays down the limitations on what the government can do or cannot do.
• Set of Rights – A constitution lists the rights of the citizens, means for protection of this rights and the duties of citizens. It also lists the means of protecting the rights e.g., in India, the judiciary is entrusted with protecting the rights. The rights guaranteed by the constitution are not unlimited i.e. they are subject to reasonable limitations. 
• Set of Objectives and Values – A constitution enumerates the values and objectives that it seeks to fulfill. For e.g., Indian Constitution seeks to ensure the values of justice, liberty and equality.