DYFALU: A Welsh term for a form of fanciful conceit in which a string of sequential metaphors compares an object to a number of diverse things--often using compound words in a manner similar to the Anglo-Saxon or Old Norse kenning.
A comedy, in contrast to a tragedy, is a genre of drama in literature that is characterized by its happy and vivacious ending. Besides making the audience happy, a comedy rather importantly intends to evoke humour and amusement in the audience by means of extensive laughter.
1 Depending on how you count certain plays, Shakespeare wrote more histories than anything.  Tragedies are very serious plays that typically involve royalty (or others of very high social station) and depict the deaths of multiple main characters.