Au, AU or au may refer to:
Australia (/əˈstreɪliə/, /ɒ-/, /-ljə/), officially the Commonwealth of Australia, is a country comprising the mainland of the Australian continent, the island of Tasmania and numerous smaller islands.
Automation or automatic control, is the use of various control systems for operating equipment such as machinery, processes in factories, boilers and heat treating ovens, switching on telephone networks, steering and stabilization of ships, aircraft and other applications and vehicles with minimal or reduced human intervention.
Austria (/ˈɒstriə, ˈɔː-/; German: Österreich [ˈøːstɐˌʁaɪç]), officially the Republic of Austria (German: Republik Österreich, listen ), is a federal republic and a landlocked country of over 8.7 million people in Central Europe.
Augustus (Latin: Imperātor Caesar Dīvī Fīlius Augustus; 23 September 63 BC – 19 August 14 AD) was the founder of the Roman Principate and considered the first Roman emperor, controlling the Roman Empire from 27 BC until his death in AD 14.
Austin (/ˈɒstᵻn, ˈɔː-/) is the capital of the U.S. state of Texas and the seat of Travis County, although portions of the city extend into Hays and Williamson counties.