Java (Indonesian: Jawa) is an island of Indonesia and the site of its capital city, Jakarta. Once the centre of powerful Hindu kingdoms, Islamic sultanates, and the core of the colonial Dutch East Indies, Java now plays a dominant role in the economic and political life of Indonesia. Home to 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. If the island were a country, it would be the tenth most populous in the world, just ahead of Japan.
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, though Javanese is dominant and is the native language of 60 million people in Indonesia, most of whom live on Java. 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.