Some go to learn, to be taught a moral lesson. One way to classify the legitimate theatre is by type of staging. The scene of action is framed by a proscenium arch, and the front curtain represents the fourth wall of the stage room. When the curtain opens, the audience looks through this fourth wall into the room. The thrust stage also known as the open, or platform, stage extends into the audience.
Spectators sit on three sides.
Often this type is combined with proscenium staging. Part of the action takes place in front of the curtain line and part behind. Theatre in the round is also called arena, or central, stage. The action takes place on a platform space or on the floor in the center of the room. The audience completely encircles the playing space.