What is a proscenium arch stage?

A proscenium arch stage is the modern traditional stage you see in most dedicated theatrical venues. The proscenium is a wall with a large arch where the main curtain line separates the "house" (where the audience sits) from the "onstage" (containing the main stage acting area and the backstage area).

Usually there is more stage extending into the house area called a "thrust." Between the audience and thrust stage is the orchestra pit or simply the "Pit" where musicians can play for the audience without blocking the audience's view from the actors.

Backstage, there is a "shop" where sets can be constructed before a production or stored during a performance. The "fly system" or "fly's" is a series of pulleys and weights which can raise or lower set pieces from the "grid" (located above the main stage). The light booth and sound booth are located usually behind the audience, a location known as "front of house," and also considered a backstage area.