The Constitution of India describes India as a Union of States.

The Constitution of India, adopted on 26th January 1950, defines the political structure and governance of the country. It begins with the preamble which clearly states that India is a "sovereign, socialist, secular, and democratic republic". The preamble also declares that India is a "Union of States". This signifies that India is a federal country with a strong central government.

Explanation:

1. Union of States:
The term "Union of States" signifies that India is a federation of states. It implies that the country is formed by the coming together of various states and their voluntary association with the central government. Each state has its own government and legislative assembly, which governs and legislates on matters pertaining to the state. However, these states are not completely independent and have to function within the framework of the Constitution of India.

2. Federal Features:
Although India is described as a Union of States, it is often referred to as a "quasi-federal" or "federal" country. This is because the Indian Constitution contains several features of federalism. For example:
- Division of powers: The Constitution clearly demarcates powers between the central government and state governments. There are three lists - Union List, State List, and Concurrent List, which outline the subjects on which each level of government can legislate.
- Bicameral legislature: India has a bicameral legislature at the national level, consisting of the Rajya Sabha (Council of States) and the Lok Sabha (House of the People). This is a feature of federalism where both the central and state governments have representation in the legislative process.
- Independent judiciary: The Constitution establishes an independent judiciary to interpret and safeguard the federal provisions of the Constitution. The Supreme Court of India acts as the guardian of the Constitution and resolves disputes between the central government and state governments.

3. Strong Center:
Despite having federal characteristics, India also has a strong central government. This means that the central government has significant powers and authority over the state governments. For example:
- Residuary powers: In case of any conflict or ambiguity, the central government has the authority to make laws on matters not specifically mentioned in any list.
- Emergency powers: During times of emergency, the central government can assume control over the functioning of the states and take necessary measures for the welfare of the country.
- Single Constitution: Unlike some federal countries that have separate constitutions for the central and state governments, India has a single Constitution that applies to both levels of government.

Conclusion:
In conclusion, the Constitution of India describes India as a Union of States, which signifies that India is a federal country with a strong central government. It has federal features such as division of powers, bicameral legislature, and independent judiciary, but the central government has significant powers and authority over the state governments. This unique blend of federalism and a strong center makes India a quasi-federal country.