In architecture, a hypostyle hall has a roof which is supported by columns, as in the Great Hypostyle Hall at Karnak. The word hypostyle comes from the Ancient Greek hypóstȳlos meaning "under columns" (where hypó means below or underneath and stŷlos means column).[1] The roof may be constructed of with bridging lintels of stone, wood or other rigid material such as cast iron, steel or reinforced concrete. There may be a ceiling. The columns may be all the same height or, as in the case of the Hypostyle Hall at Karnak, the columns flanking the central space may be of greater height than those of the side aisles, allowing openings in the wall above the smaller columns, through which light is admitted over the aisle roof, through clerestory windows.
The architectural form has many applications, occurring in the cella of Ancient Greek temples and in many Asian buildings, particularly of wood construction. With a combination of columns and arches, the hypostyle hall became one of the two main types of mosque construction. The hypostyle is widely used in modern architecture.