Chapter 1 provides an overview of possible answers to the question of its title by establishing the terminology, then moving through considerations of what one might call the opera industry and the institutions that support it, of the artists who engage in it in the theater, of the repertory from the Baroque period to modern times, and of the issues and techniques that might underpin a given libretto and how it is set to music. This leads to a discussion of the oft-claimed exoticism and irrationality of opera and how one might best respond.