Melbourne is the capital and most populous city in the state of Victoria, and the second most populous city in Australia.The Melbourne City Centre (also known as the "Central Business District" or "CBD") is the hub of the greater geographical area (or "metropolitan area") and the Census statistical division-of which "Melbourne" is the common name. As of June 2009, the greater geographical area had an approximate population of four million. Inhabitants of Melbourne are called Melburnians.

The metropolis is located on the large natural bay known as Port Phillip, with the city centre positioned at the estuary of the Yarra River (at the northern-most point of the bay). The metropolitan area then extends south from the city centre, along the eastern and western shorelines of Port Phillip, and expands into the hinterland. The city centre is situated in the municipality known as the City of Melbourne, and the metropolitan area consists of a further 30 municipalities.

It was founded in 1835 (47 years after the European settlement of Australia) by settlers from Van Diemen's Land. It was named by governor Richard Bourke in 1837, in honour of William Lamb-the 2nd Viscount Melbourne. Melbourne was officially declared a city by Queen Victoria in 1847. In 1851, it became the capital city of the newly created colony of Victoria. During the Victorian gold rush of the 1850s, it was transformed into one of the world's largest and wealthiest cities. After the federation of Australia in 1901, it then served as the interim seat of government of the newly created nation of Australia until 1927.

Today, it is a centre for the arts, commerce, education, entertainment, sport and tourism. It is the birthplace of cultural institutions such as Australian film (as well as the world's first feature film), Australian television, Australian rules football, the Australian impressionist art movement (known as the Heidelberg School) and Australian dance styles (such as New Vogue and the Melbourne Shuffle). It is also a major centre for contemporary and traditional Australian music. It is often referred to as the "cultural capital of Australia".

Melbourne has been ranked as one of the top three World's Most Livable Cities by the Economist Group's Intelligence Unit (since 2002), top 10 Global University Cities by RMIT's Global University Cities Index (since 2006) and top 20 Global Innovation Cities by the 2thinknow Global Innovation Agency (since 2007). The metropolis is also home to the world's largest tram network. The main airport serving Melbourne is Melbourne Airport.