This document provides an overview of literary theory and criticism from classical times to modern eras. It begins with definitions of literary theory and criticism, noting that theory provides conceptual frameworks for studying literature while criticism is the practical application and evaluation of works. Major figures from classical antiquity discussed include Plato, Aristotle, Longinus, and Horace, along with their contributions to early understandings of genres, imitation, and literature's functions. The document then outlines developments from the Renaissance through the Victorian era, highlighting influential critics such as Sidney, Jonson, and Dryden. It concludes by listing various modern critical theories and theorists that reflect the expansion of literary study in the 20th century.