Indian Union:
The Indian Union refers to the political and administrative organization of India as a federal union of states. It is the constitutional framework that governs the relationship between the central government and the states of India. The Indian Union is based on the principles of federalism, which means that power is divided between the central government and the state governments.

Indian Mainland:
The Indian mainland refers to the main part of the Indian subcontinent, which is located in South Asia. It is the landmass that comprises the majority of the territory of India. The Indian mainland is bordered by the Arabian Sea on the west, the Bay of Bengal on the east, and the Indian Ocean on the south.

India - Size And Location:
India is the seventh-largest country in the world by land area and the second-most populous country. It is located in South Asia, between latitudes 8°4' and 37°6' north and longitudes 68°7' and 97°25' east. India shares its borders with several countries, including Pakistan to the northwest, China and Nepal to the north, Bhutan to the northeast, and Bangladesh and Myanmar to the east.

Key Points:
1. Area: India has a total area of about 3.28 million square kilometers, which includes the Indian mainland and several offshore islands.
2. Coastline: India has a coastline of about 7,516.6 kilometers, including the mainland coastline and the coastlines of the Andaman and Nicobar Islands and Lakshadweep Islands.
3. Standard Meridian: The Standard Meridian of India is 82°30' E, which passes through the city of Allahabad.
4. Time Zone: India follows the Indian Standard Time (IST), which is 5 hours and 30 minutes ahead of Coordinated Universal Time (UTC+5:30).
5. Tropic of Cancer: The Tropic of Cancer passes through the middle of India, dividing the country into two climatic regions - the tropical region to the south and the subtropical region to the north.
6. Geographical Divisions: India can be divided into several geographical divisions, including the Northern Mountains, the Northern Plains, the Peninsular Plateau, the Coastal Plains, and the Islands.

In conclusion, the Indian Union is the federal political and administrative organization of India, while the Indian mainland refers to the main part of the Indian subcontinent. India's size and location make it a unique and diverse country, with a rich geographical and cultural heritage.

What is mainland