Guam (Chamorro: Guåhån), officially the Territory of Guam, is an island in the Western Pacific Ocean and is an organized unincorporated territory of the United States. Its inhabitants are the Chamorros, who first populated the island approximately 3,500 years ago. It is the largest and southernmost of the Mariana Islands. The capital is Hagåtña, formerly Agana (pronounced Agaña). Guam's economy is mainly supported by tourism (particularly from Japan) and United States armed forces bases. The latter takes up one-third of the entire land mass of the island. The United Nations Committee on Decolonization includes Guam on the United Nations list of Non-Self-Governing Territories.

Source: www.wikipedia.org