Papua New Guinea is officially called the Independent State of Papua New Guinea. It occupies half of the island of New Guinea (the world’s second largest island). It is one of the most culturally diverse countries in the world, with 848 different languages spoken, of which 12 have no known living speakers. It is also one of the world’s least explored countries, culturally and geographically. Many people live in extreme poverty, and a majority of the population still live in traditional societies and practice subsistence-based agriculture. It established its sovereignty in 1975, and became a separate Commonwealth realm (headed by Queen Elizabeth II). It has an area of 462,840 sq km, a population of 7 million, and a low HDI of 0.466.