Greek architecture progressed through three main periods - Early, Classical, and Hellenistic. Early architecture was rough with different masonry styles. Classical architecture saw the refinement of columns and architectural orders like Doric and Ionic. Hellenistic architecture saw the increased use of the Corinthian order and other refinements. Key structures included temples, theaters, and agoras. Major temples included the Parthenon, with its refined proportions and sculptural details, and the Erechtheion, known for its asymmetrical style and Caryatid columns. Greek buildings employed various optical illusions and refinements for proportional accuracy.