This document discusses different types of theatre stages. It describes proscenium stages as having an architectural frame known as the proscenium arch, with the stage gently sloping away from the audience. Thrust stages project into the auditorium with audiences on three sides. Theatres-in-the-round have performance areas enclosed by audiences on all sides, with actors entering through aisles. Black-box or studio theatres are flexible performance spaces that are essentially a single painted black room. Platform stages usually consist of a raised rectangular platform at one end of a room facing rows of seating.