Australia ( , or formally ), officially the Commonwealth of Australia, is a country in the southern hemisphere comprising the mainland of the world's smallest continent, the major island of Tasmania, and numerous other islands in the Indian and Pacific Oceans.ref: N4 Neighbouring countries include Indonesia, East Timor, and Papua New Guinea to the north, the Solomon Islands, Vanuatu, and New Caledonia to the north-east, and New Zealand to the south-east.

For around 40,000 years before European settlement commenced in the late 18th century, the Australian mainland and Tasmania were inhabited by around 250 individual nations of indigenous Australians. After sporadic visits by fishermen from the immediate north, and European discovery by Dutch explorers in 1606, the eastern half of Australia was claimed by the British in 1770 and initially settled through penal transportation to the colony of New South Wales, founded on 26 January 1788. The population grew steadily in the following years; the continent was explored, and during the 19th century another five largely self-governing Crown Colonies were established.

On 1 January 1901, the six colonies became a federation, and the Commonwealth of Australia was formed. Since Federation, Australia has maintained a stable liberal democratic political system and remains a Commonwealth realm. The population is just over 21.7 million, with approximately 60% concentrated in and around the mainland state capitals of Sydney, Melbourne, Brisbane, Perth, Adelaide, and Darwin. The nation's capital city is Canberra, located in the Australian Capital Territory (ACT).

Technologically advanced and industrialised, Australia is a prosperous multicultural country and has excellent results in many international comparisons of national performance such as health care, life expectancy, quality-of-life, human development, public education, economic freedom, and the protection of civil liberties and political rights. Australian cities also routinely rank among the world's highest in terms of livability, cultural offerings, and quality of life. It is a member of the United Nations, G-20 major economies, Commonwealth of Nations, ANZUS, OECD, and the WTO.

Etymology

The name Australia is derived from the Latin Australis, meaning "Southern". Legends of an "unknown land of the south" (terra australis incognita) date back to Roman times and were commonplace in medieval geography but were not based on any documented knowledge of the continent. In 1521 Spaniards were among the first Europeans to sail the Pacific Ocean. The first use of the word Australia in English was in 1625, in "A note of Australia del Espiritu Santo, written by Master Hakluyt", published by Samuel Purchas in Hakluytus Posthumus. The Dutch adjectival form Australische was used by Dutch East India Company officials in Batavia to refer to the newly discovered land to the south in 1638. Australia was used in a 1693 translation of Les Aventures de Jacques Sadeur dans la Découverte et le Voyage de la Terre Australe, a 1676 French novel by Gabriel de Foigny under the pen-name Jacques Sadeur.