India is the most populous country on earth, with over 1.4 billion people. That figure means little until you experience the reality of it: the density of Indian cities, the constant press of humanity at railway stations and markets, and the extraordinary diversity that comes from fitting this many people into one country.
Hinduism is practiced by roughly 80% of the population. Islam is the faith of about 14%, making India home to one of the world's largest Muslim populations — some 200 million people. Christianity, Sikhism, Buddhism, and Jainism all have significant followings; the subcontinent was the birthplace of several of these religions.
The social structure is still heavily shaped by the caste system, though its legal standing has been progressively dismantled since independence and attitudes — especially in cities and among younger generations — have shifted considerably. Caste remains relevant in rural areas and in marriage decisions across social classes.
India is genuinely multilingual. There are over 20 constitutionally recognized languages and some estimates count hundreds of distinct languages and thousands of dialects. Hindi (in various forms) is the lingua franca of the north. Tamil, Telugu, Kannada, and Malayalam dominate the south, where Hindi is less widely spoken than English. Bengali, Gujarati, Marathi, Punjabi, and Assamese each have tens of millions of speakers.
The literacy rate is around 77% overall, with significant gaps between states (Kerala is over 95%) and between urban and rural populations. English-language education is widespread at secondary level and above in cities, which is why India has such a large professional class that communicates in English with ease.
Indian hospitality is genuine. Strangers on trains will share food, ask endless questions about your life, and offer opinions on everything. Saying no to tea is almost impolite. If someone invites you to their home, accept if you can — the experience of sharing a meal in an Indian family's house is worth more than most sights on the tourist trail.