The Indian economy is the world’s tenth-largest by nominal GDP and third-largest by purchasing power parity (PPP). Following market-based economic reforms in 1991, India became one of the fastest-growing major economies; it is considered a newly industrialised country. However, it continues to face the challenges of poverty, corruption, malnutrition, inadequate public healthcare, and terrorism. A nuclear weapons state and a regional power, it has the third-largest standing army in the world and ranks eighth in military expenditure among nations. India is a federal constitutional republic governed under a parliamentary system consisting of 29 states and 7 union territories. India is a pluralistic, multilingual, and a multi-ethnic society. It is also home to a diversity of wildlife in a variety of protected habitats.