Apartment

Tenement law refers to the feudal basis of permanent property such as land or rents. May be found combined as in "Messuage or Tenement" to encompass all the land, buildings and other assets of a property.
In the US and Canada, some apartment-dwellers own their own apartments, either as co-ops, in which the residents own shares of a corporation that owns the building or development; or in condominiums, whose residents own their apartments and share ownership of the public spaces. Most apartments are in buildings designed for the purpose, but large older houses are sometimes divided into apartments. The word apartment connotes a residential unit or section in a building. In some locations, particularly the United States, the word denotes a rental unit owned by the building owner, and is not typically used for a condominium.
In the UK, some flat owners own a share in the company that owns the freehold of the building. This is commonly known as a "share of freehold" flat. The freehold company has the right to collect annual ground rents from each of the flat owners in the building. The freeholder can also develop or sell the building, subject to the usual planning and restrictions that might apply.
In some countries the word unit is a more general term referring to both apartments and rental business suites. The word is generally used only in the context of a specific building; e.g., "This building has three units" or "I'm going to rent a unit in this building", but not "I'm going to rent a unit somewhere." In Australia, a unit refers to flats, apartments or even semi-detached houses. Some buildings can be characterized as mixed use buildings, meaning part of the building is for commercial, business, or office use, usually on the first floor or first couple floors, and there are one or more apartments in the rest of the building, usually on the upper floors.