This document discusses Byzantine architecture, mosaics, and icons. It describes the key characteristics of Byzantine architecture as being influenced by Greek and Roman styles and using semi-circular arches, domes, and basilica and Greek cross floor plans. It provides examples of important Byzantine buildings like Hagia Sophia and St. Mark's Basilica. Mosaics are described as using bright colors with religious themes on walls and ceilings. Icons are defined as religious paintings on wood with gold backgrounds and rigid, frontal poses with no expression.