A storey or story is any level part of a building with a floor that could be used by people. The plurals are "storeys" and "stories", respectively. — The terms "floor", "level", or "deck" are used in a similar way, except …
A large elevator panel in a North American high-rise omits several floors as well as designating three separate levels as penthouse floors.
An elevator control panel in an apartment building in Shanghai. Floors 4, 13 and 14 are missing.
Letter boxes of a residential building built in the 1970s in Hong Kong. The Chinese and English floor numberings use the traditional Chinese and the British systems, respectively, resulting in different numbers.
A Dover Custom Impulse Elevator control panel with floor numbering. In most buildings in the US and Canada, there is no thirteenth floor. The ☆ indicates the main entry floor.