They can provide general room lighting, and are common in hallways and corridors, but they may be mostly decorative. A scone may be a traditional torch, candle or gaslight, or a modern electric light source affixed in the same way.
Scones can be placed on both the interior and exterior walls of buildings. In pre-modern usage, these usually held candles and torches respectively. Historically, candle scones were often made of silver or brass from the 17th century, with porcelain and ormolu coming into use during the 18th century. The light of the candle flame was often intensified by a reflecting backplate. Using brackets, the candle would be kept at a safe distance from the wall.
Modern electric light fixture scones are often used in hallways or corridors to provide both lighting and a point of interest in a long passage. Scone height in a passageway is generally 3/4 of the distance up the wall as measured from the floor to the ceiling, and the distance between scones on the wall is generally equal to the distance of the scones from the floor, often alternating sides of the passageway.
Scones are typically installed in pairs or other multiple units to provide balance. They can be used to frame doorways or line a hallway. Swing-arm scones are often placed next to a bed to provide task lighting for reading.