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 (or sometimes a train) support the activity to be conducted in it.
I'm going to blow out the walls of an existing storage 8'x6' room in the basement to make a bigger 11'x8' storage room. It won't be used a lot. but it'll need a ceiling light and a wall outlet or two.
It's on two outside walls, but it does have two adjoining rooms with electrical service (some...