In a building or ship, a room is any enclosed space within a number of walls to which entry is possible only via a door or other dividing structure. The entrance connects it to either a passageway, another room, or the outdoors. The space is typically large enough for several people to move about. The size, fixtures, furnishings, and sometimes placement of the room within the building or ship support the activity to be conducted in it.

A wall is a structure and a surface that defines an area; carries a load; provides security, shelter, or soundproofing; or, is decorative. There are many kinds of walls, including:Walls in buildings that form a fundamental part of the superstructure or separate interior rooms, sometimes for fire safety Glass walls Border barriers between countries Brick walls Defensive walls in fortifications Permanent, solid fences Retaining walls, which hold back dirt, stone, water, or noise sound Stone walls Walls that protect from oceans (seawalls) or rivers (levees)