Allegory:

The more or less extended use of metaphor, symbol, or personification for the purpose of communicating indirectly a hidden meaning—often a veiled personal identity, political opinion, or religious or moral doctrine.

Dream Allegory:

An allegory set in the framework of a dream or vision.

Exemplum:

A moral tale that usually, though not necessarily, embellishes a sermon or homily.

Fabliau:

A short, humorous, sometimes bawdy story, usually in verse, which deals with middle or lower-class life.

Fable:

A brief story that emphasizes a moral.

Lay (Lai):

A short poem, usually a romantic narrative, intended to be sung or recited by a minstrel.

Romance:

A tale of chivalric adventure, in verse or prose, usually set in a remote time or place and including elements of the supernatural or fantastic. Romances in verse are sometimes called "metrical romances."
Matter of France: Tales surrounding the life and deeds of Charlemagne (742-814)

Matter of Britain: Tales about King Arthur and the Round Table.

Matter of Rome: Tales about Alexander or other classical figures.

Satire:

A work in verse or prose aiming to expose and correct personal, social or spiritual follies or vices.

Mystery Play:

A play based upon scripture or sacred history.

Miracle Play:

A play about the miracles attributed to saints.

Morality Play:

An allegory in which some or all of the characters are abstractions, such as the seven deadly sins.

Folk Ballad:

An oral narrative in verse telling a compact and allusive story; it incorporates formulaic themes (love and death) and is marked by the use of incremental repetition.