Final answer:
Greek theaters were often built into hillsides and featured a circular orchestra and a temporary skene, later replaced by a permanent stone structure. Roman theaters had semi-circular orchestras, deeper stage areas, and elevated stages for more complex entertainment, seating much larger crowds.
Step-by-step explanation:
Typically, what differentiates a Greek-style theater from its Roman counterpart is the elevation of the stage. Greek theaters often utilized the natural slope of a hillside for the seating area, with a circular orchestra at the bottom where the chorus performed and an altar for sacrifices in the center. A temporary wooden structure called the skene was situated behind the orchestra, which later became a permanent stone building with three doors for actors' entrances and exits. In contrast, Roman theaters had an orchestra that was semi-circular and a deeper and wider stage area, with a permanent facade behind the stage (scaenaefrons) that often included complex scenery and mechanical engineering advances, such as elevators and ramps, to accommodate more spectacular forms of entertainment. Roman theaters also were built to accommodate much larger audiences, with some seating over 40,000 spectators, and they featured more elevated stages to facilitate the visibility of performances that leaned towards aggressive pantomime and physical action. The use of an elevated stage is a key feature that distinguishes Roman theaters from Greek theaters, which often did not have such significant elevation differences between the stage and the orchestra.