An apartment (American English), flat (British English, Indian English, South African English), or unit (Australian English), is a self-contained housing unit (a type of residential real estate) that occupies part of a building, generally on a single storey. There are many names for these overall buildings, see below. The housing tenure of apartments also varies considerably, from large-scale public housing, to owner occupancy within what is legally a condominium (strata title or commonhold), to tenants renting from a private landlord (see leasehold estate).
“Mixed-use buildings” combine commercial and residential uses within the same structure. Typically, mixed-use buildings consist of businesses on the lower floors (often retail in street-facing ground floor and supporting subterranean levels) and residential apartments on the upper floors.