Preamble is nothing but an introduction to any statute. Same as the case in Constitution. Preamble is useful in the understanding of the policy and intention of the legislature. In other words, we can say that, Preamble is the key to the Constitution.
Preamble sets out the main objectives which the legislature seeks to secure for the people of the nation. It is the legitimate aid in construction of the provisions of the Constitution. Preamble contains the ideals and aspirations which the framers of the Constitution wanted for general purpose of the people in their best interest.
Preamble usually throws useful lights as to what a statute intends to teach. In other words, it lays down the objectives of the statutes which the legislature intends to achieve. However, the Preamble of an Act is not generally recognized as a part of the Act, because, the same is not enacted OR adopted by the enacting body in the same way as that of enacting provisions.Thus the question is;
Whether, the Preamble is a part of the Constitution or not?
In Berubari Case, the Honourable Supreme Court of India expressed the opinion that, a Preamble was not a part of the Constitution. However, in Kesavananda Bharathi case, Honourable Supreme Court of India changed its opinion and held that, Preamble is apart of the Constitution and relates to its basic structure and should be read and interpreted in the light of grand and noble vision expressed in the preamble.