Theater is a collaborative art form that uses live performers to present real or imagined events. It originated in ancient Greece around 532 BC. There are several types of theater structures including arena, flexible, and proscenium theaters. Naturalism and expressionism were early modern movements that sought to realistically or expressionistically portray life influences. Theater provides benefits such as bringing people together, modeling democratic discourse, contributing to education, supporting the economy, and encouraging self-reflection.