The Preamble to the Constitution of India declares India a Sovereign, Socialist, Secular, Democratic, Republic State.
The word sovereign implies that India is a free nation and independent to conduct its own affairs without any interference.
The term Socialist was added by the 42nd Constitutional Amendment Act, 1976. India is a democratic socialistic state meaningly that it works for the welfare of all people and sustains both public and private sectors for the growth of Nation. The Directive Principle represents the socialistic nature of India.
Democratic in the sense that the Supreme power lies in the people of India. India has a Parliamentary democracy where the people elect their representatives to make laws and policies for the nation.
It is Republic as the Head of the state called President is elected indirectly by the people for a fixed term of five years.