A municipality is an administrative entity composed of a clearly defined territory and its population and commonly denotes a city, town, or village, or a small grouping of them. A municipality is typically governed by a mayor and a city council or municipal council. The notion of municipality includes townships but is not restricted to them. A municipality is a general-purpose district, as opposed to a special-purpose district. In most countries, a municipality is the smallest administrative subdivision to have its own democratically elected representative leadership. In some countries, municipalities are referred to as "communes". The term derives from the medieval commune. In some countries, especially in the Middle East, the term "municipality" is also used to refer to the municipal administrative building known elsewhere as the town hall or city hall. The largest municipalities can be found in Canada, Greenland, Australia and Brazil.