The term may be used in general to describe any drawing showing the physical layout of objects. For example, it may denote the arrangement of the displayed objects at an exhibition, or the arrangement of exhibitor booths at a convention. Now drawings are reproduced using plotters and large format xerographic copiers.
It is also called a "plan" in architectural terms, as opposed to "elevation" which means how the object will look when seen from a side, or a "cross section" where the building is shown cut along an axis to reveal the interior.
A "reflected ceiling plan" shows a view of the room as if looking from above, through the ceiling, at a mirror installed one foot below the ceiling level, which shows the reflected image of the ceiling above. This convention maintains the same orientation of the floor and ceilings plans - looking down from above. Reflected Ceiling Plans or RCP's are used by designers and architects to demonstrate lighting, visible mechanical features, and ceiling forms as part of the documents provided for construction.