Short answers, pulled from the story.
India gained independence from British rule in 1947, when the British Indian Empire was partitioned into two dominions: India and Pakistan. India adopted its constitution in 1950 and became a federal, secular, democratic republic. The constitution came into effect on the 26th of January 1950.
India is the world's most populous country, with an estimated 1,428,627,663 residents in 2023. Its population grew from 361 million counted in the first post-colonial census in 1951, with the decennial growth rate slowing over time: the population grew by 21.54% between 1991 and 2001, then by 17.64% between 2001 and 2011.
Hindi in the Devanagari script is the official language of India's federal government, with English as an associate official language. The Eighth Schedule of the constitution recognises 22 languages the government is obligated to develop, a list that grew from 14 languages in 1950 through successive constitutional amendments, most recently adding Maithili, Dogri, Santali, and Bodo in 2004.
Four major world religions originated on the Indian subcontinent: Buddhism, Hinduism, Jainism, and Sikhism. According to the 2011 census, 79.8% of India's population follows Hinduism, 14.2% Islam, 2.3% Christianity, 1.7% Sikhism, 0.7% Buddhism, and 0.4% Jainism. India also holds the world's largest populations of Zoroastrians and Baha'i Faith adherents.
Indian mathematicians first recorded the decimal number system, the concept of zero as a number, negative numbers, and the modern definitions of sine and cosine. The Sulba Sutras of approximately 700-400 BCE contain the earliest known written expression of the Pythagorean theorem. In the 15th century, scholars of the Kerala school developed power series expansions for trigonometric functions, two centuries before calculus emerged in Europe.
India's nominal GDP per capita rose from US$64 annually at independence to an estimated US$2,731 in 2024, after an acute balance of payments crisis in 1991 forced liberalisation from a protectionist, state-regulated model. Some 431 million Indians left poverty between 1985 and the mid-2020s. By 2022 India had become the world's third-largest vehicle market and received US$100 billion in foreign remittances, the highest in the world that year.