An apartment (in American and Canadian English) or a flat (in British English) is a self-contained housing unit (a type of
residential real estate) that occupies only part of a building, correctly, on a single level without a stair. Such a building may
be called an apartment building, apartment complex, apartment house (in American English), block of flats, tower block,
high-rise or, occasionally mansion block (in British English), especially if it consists of many apartments for rent. In Scotland
it is called a block of flats or, if it''s a traditional sandstone building, a tenement, which has a pejorative connotation
elsewhere. Apartments may be owned by an owner/occupier, by leasehold tenure or rented by tenants (two types of housing
tenure).