Preamble is very important part of our Constitution. Just like a book starts with a preface, similarly our Constitution starts with its preamble. Preamble gives objectives, desires and expectations from our Constitution. We have borrowed this feature from the Constitution of U.S.A.
The Preamble clearly shows that this Constitution has been made by the people of India. The People of India is sovereign in our Country. The objectives of our Constitution are to establish India as a sovereign, socialist, secular, Democratic Republic and to secure Justice, liberty, equality & Fraternity to its all citizens.
Supreme Court in Beru Bari case 1960, ruled that preamble is not a part of our Constitution but in Keshvanand Bharti case 1973, Supreme Court changed its ruling and said that preamble is a part of our Constitution and preamble narrates the objectives and aspirations of our Constitution.
Our preamble has been amended once by 42nd Constitution Amendment Act 1976. Three new words were added in our Constitution Socialist, Secular and integrity to make it very clear that we want to established a socialistic society to avoid concentration of wealth in few hands and benefit of development must reach to all sections of the society. Similarly our aim is to establish a secular State with respect to all religions but no religion of the State and integrity of our country is of utmost importance to us.