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Scenarios from WikiPedia:

A scenario (from Italian, that which is pinned to the scenery) is a synthetic description of an event or series of actions and events. In the Commedia dell'arte it was an outline of entrances, exits, and action describing the plot of a play that was literally pinned to the back of the scenery. It is also known as canovaccio or "that which is pinned to the canvas" of which the scenery was constructed.

Surviving scenarios from the Renaissance contain little other than character names, brief descriptions of action, and references to specific lazzi with no further explanation. It is believed that a scenario forms the basis of a fully improvisational performance though it is also likely that they were simple reminders of the plot for those members of the cast who were literate. Modern commedia troupes most often make use of a script with varying degrees of additional improvisation (see improvisational theatre).

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