Australia, 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.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[7] of indigenous Australians.[8] After sporadic visits by fishermen from the immediate north, and European discovery by Dutch explorers in 1606,[9] 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, and Adelaide. 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.[10] 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.
澳大利亚，全名澳大利亚联邦（英文：Commonwealth of Australia），是全球地理面积第六大国家、大洋洲最大国家。其国境东南邻近新西兰，西北邻近印度尼西亚，北边靠近巴布亚新几内亚、西巴布亚和东帝汶。
“澳大利亚”一词源于拉丁语“未知的南方大陆”（terra australis incognita）。其所在的地理学位置通常称作澳大利亚大陆，是地球上最小的大陆板块。其人民平均拥有国土面积乃世界最广国家之一，经济成就亦属世界高度发达国家。国民生活水平很高，经济的主要重点是高效率的能源和畜牧业。
澳大利亚有多样的自然景观，包括迷人的热带雨林、别称“红色中央”的干燥贫瘠的沙漠，白雪皑皑的山峰、绵羊遍布的牧场、及引人入胜的海滨，和驰名遐迩的自然遗产大堡礁、乌鲁汝。在每年世界最佳居住城市评选中，澳大利亚名列前茅的城市数目在全球国家之先。