Slide 42 -
Orchestra: The orchestra (literally, "dancing space") was normally circular. It was a level space where the chorus would dance, sing, and interact with the actors who were on the stage near the skene. The earliest orchestras were simply made of hard earth, but in the Classical period some orchestras began to be paved with marble and other materials. In the center of the orchestra there was often a thymele, or altar. The orchestra of the theater of Dionysus in Athens was about 60 feet in diameter.
Theatron: The theatron (literally, "viewing-place") is where the spectators sat. The theatron was usually part of hillside overlooking the orchestra, and often wrapped around a large portion of the orchestra (see the diagram above). Spectators in the fifth century BC probably sat on cushions or boards, but by the fourth century the theatron of many Greek theaters had marble seats.
Skene: The skene (literally, "tent") was the building directly behind the stage. During the 5th century, the stage of the theater of Dionysus in Athens was probably raised only two or three steps above the level of the orchestra, and was about 25 feet wide and 10 feet deep. The skene was directly in back of the stage, and was usually decorated as a palace, temple, or other building, depending on the needs of the play. It had at least one set of doors, and actors could make entrances and exits through them. There was also access to the roof of the skene from behind, so that actors playing gods and other characters could appear on the roof, if needed.
Parodos: The parodoi (literally, "passageways") are the paths by which the chorus and some actors (such as those representing messengers or people returning from abroad) made their entrances and exits. The audience also used them to enter and exit the theater before and after the performance.