A condo is a home inside a larger building — a flat — but the North American idea is that you buy that one unit and own it. The halls, the lift, the garden, the roof are shared, and you usually pay a fee for that shared part. It is the short, everyday form of condominium, and it sounds informal: “They bought a condo in Miami.” You hear it most in the US and Canada. British English more often says flat, and does not use condo as much. An apartment, in American talk, is often the one you rent; a condo is the one you own, though people are not always that tidy in real life. Though actually, condominium first named a place under shared rule (two countries sharing power over one land). Only later did it name a building where many people each own a piece. The short form condo is the one friends and adverts use; condominium is the full, slightly official word.

公寓（美式口語，多指買下來、有產權的那一種，和純出租的 apartment 不一樣）