Opera seria was elevated in tone and highly stylised in form, usually consisting of secco recitative interspersed with long da capo arias.
These afforded great opportunity for virtuosic singing and during the golden age of opera seria the singer really became the star. The role of the hero was usually written for the high-pitched male castrato voice,which was produced by castration of the singer before puberty, which prevented a boy's larynx from being transformed at puberty. Castrati such as Farinelli and Senesino, as well as female sopranos such as Faustina Bordoni, became in great demand throughout Europe as opera seria ruled the stage in every country except France. Farinelli was one of the most famous singers of the 18th century.
Italian opera set the Baroque standard. Italian libretti were the norm, even when a German composer like Handel found himself composing the likes of Rinaldo and Giulio Cesare for London audiences. Italian libretti remained dominant in the classical period as well, for example in the operas of Mozart, who wrote in Vienna near the century's close. Leading Italian-born composers of opera seria include Alessandro Scarlatti, Vivaldi and Porpora.