What are the main differences between opera seria and opera buffa?

In the 18th century, Italian opera was divided into two primary genres: opera seria and opera buffa. Their differences are rooted in subject matter, structure, and social intent.

Opera Seria

Known as "serious opera," this genre was the dominant, conventionalized form of the era.12
* Subject Matter: Plots were typically heroic, tragic, or legendary, often based on Greco-Roman history or mythology.31
* Structure: It followed a rigid, formal structure designed to showcase vocal virtuosity. It featured a limited number of characters (usually six) and relied heavily on a succession of da capo arias that interrupted the dramatic flow.12
* Style: It emphasized elevated language and formal beauty, with little use of the chorus or complex orchestral accompaniment.12

Opera Buffa

Originating in Naples, this "comic opera" emerged as a reaction against the artificiality of opera seria.42
* Subject Matter: Plots were light, sentimental, and often satirical, focusing on a mix of comic characters and lovers.42
* Structure: It introduced more dynamic musical developments, such as the long, formally organized ensemble finale that involved all principal characters.4
* Style: The music was tuneful, accessible, and reflected contemporary social changes, often mocking the conventions of serious opera.2