The Sundanese are an ethnic group native to the western part of the Indonesian island of Java. They number approximately 40 million, and are the second most populous of all the nation's ethnicities. The Sundanese are predominantly Muslim. In their own language, Sundanese, the group is referred to as Urang Sunda, and Suku Sunda or Orang Sunda in the national language, Indonesian. The Sundanese have traditionally been concentrated in the provinces of West Java, Banten, Jakarta, and the western part of Central Java. Sundanese migrants can also be found in Lampung and South Sumatra. The provinces of Central Java and East Java are home to the Javanese, Indonesia's largest ethnic group. Sundanese culture has a number of similarities with Javanese culture, however it differs by being more overtly Islamic, with less Hindu-Buddhist elements, and has a less rigid system of social hierarchy. The common identity that binds Sundanese together is their language and culture.