Java (Indonesian: Jawa) is an island of Indonesia and the site of its capital city, Jakarta. Once the centre of powerful Hindu kingdoms and the core of the colonial Dutch East Indies, Java now plays a dominant role in the economic and political life of Indonesia. Housing a population of 130 million in 2006, it is the most populous island in the world, ahead of Honshū, the main island of Japan. Java is also one of the most densely populated regions on Earth.
Formed mostly as the result of volcanic events, Java is the 13th largest island in the world and the fifth largest island in Indonesia. A chain of volcanic mountains forms an east-west spine along the island. It has three main languages, and most residents are bilingual, with Indonesian as their second language. While the majority of Javanese are Muslim, Java has a diverse mixture of religious beliefs and cultures.