In model railroading, a layout is a diorama containing scale track for operating trains. The size of a layout varies, from small shelf-top designs to ones that fill entire rooms, basements, or whole buildings.
Attention to modeling details such as structures and scenery is common. Simple layouts are generally situated on a table, although other methods are used, including doors. More permanent construction methods involve attaching benchwork framing to the walls of the room or building in which the layout is situated.
An important aspect of any model railway is the layout of the track itself. Apart from the stations, there are four basic ways of arranging the track, and innumerable variations:
Continuous loop. A circle or oval, with trains going round and round. Used in train sets.
Point to point. A line with a station at each end, with trains going from one station to the other.
Out and back. A pear shaped track, with trains leaving a station, going round a reversing loop, and coming back to the same station.
Shunting (US: Switching). Either a station, a motive power depot or a yard where the primary mode of operation is shunting. This includes layouts which are built as a train shunting puzzle such as Timesaver and Inglenook Sidings.