Timber doors can be classified in several ways:
1) By construction - such as battened, ledged, braced, framed, panelled, glazed, flushed, louvered, wire-gauged doors.
2) By operation - such as hinged, sliding, folding, revolving doors.
3) By material - solid core, hollow core, cellular core flush doors.
Common door types include panelled doors made of wood frames enclosing timber, glass or louvered panels. Flush doors have a completely flat surface and can be solid core or hollow core varieties. Revolving doors have circular compartments that rotate around a central vertical axis.