<P> Genre should not be confused with age categories, by which literature may be classified as either adult, young adult, or children's . They also must not be confused with format, such as graphic novel or picture book . </P> <P> Just as in painting, there are different types: the landscape, the still life, the portrait; there are different types of literary works . These types tend to share specific characteristics . Genres describe those works which share specific conventions . </P> <P> Genres are often divided into subgenres . Literature, is divided into the classic three forms of Ancient Greece, poetry, drama, and prose . Poetry may then be subdivided into the genres of lyric, epic, and dramatic . The lyric includes all the shorter forms of poetry, e.g., song, ode, ballad, elegy, sonnet . Dramatic poetry might include comedy, tragedy, melodrama, and mixtures like tragicomedy . </P> <P> The standard division of drama into tragedy and comedy derives from Greek drama . This parsing into subgenres can continue: comedy has its own subgenres, including, for example, comedy of manners, sentimental comedy, burlesque comedy, and satirical comedy . </P>

What are the three main genres of literature
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