Final answer:
Theatre is a collaborative form of art that uses live performers to present experiences to an audience. It involves various elements and has evolved differently across cultures and time periods.
Step-by-step explanation:
Theatre is a collaborative form of performing art that uses live performers to present the experience of a real or imagined event to a live audience. It involves elements such as gesture, speech, song, music, and dance, and utilizes art forms like painted scenery and lighting to enhance the experience. Theatre originated from ritual and has evolved differently across cultures and time periods.