John Adams' Nixon in China, produced at the Metropolitan Opera in January 2011. Left to right: Janis Kelly as Pat Nixon, Teresa S. Herold as the Second Secretary to Mao, James Maddalena as Richard Nixon, Ginger Costa Jackson as the First Secretary to Mao, Russell Braun as Chou En-lai. Ken Howard/Metropoltan Opera hide caption
György Ligeti's surreal opera Le Grand Macabre was the hit of the New York Philharmonic's 2009-2010 season, in a semi-staged production that featured Barbara Hannigan (left) as Gepopo and Anthony Roth Costanzo as Prince Go-Go. Chris Lee/New York Philharmonic hide caption
Soprano Cheryl Barker (as Jenůfa) and tenor Peter Wedd (as Luca) sing in a production of Leoš Janáček's Jenůfa from Opera Australia. Patrick Riviere/Getty Images hide caption
In a production of Verdi's opera Rigoletto at the Sydney Opera House, the title character (baritone Jonathan Summers) reels at the discovery of his dead daughter. Patrick Riviere/Getty Images hide caption
Maria Callas, a masterful bel canto singer, performs in the title role of Bellini's Norma in Paris, May 23, 1964. AFP/Getty Images hide caption
Soprano Veronique Gens and tenor Joseph Kaiser star in a production of Gluck's Alceste at the 2010 Aix-en-Provence Festival. Anne-Christine Poujoulat/AFP/Getty Images hide caption
Baritone William Shimell sings the title role in Handel's opera Hercules in Aix-en-Provence in 2004. Boris Horvat/AFP/Getty Images hide caption
Orpheus makes his way through the underworld, in Jean-Pierre Ponnelle's production of one of the first operas, Monteverdi's L'Orfeo, from 1607. Deutsche Grammophon hide caption
Know your rallentando from your accelerando? Opera singers must follow the composer's musical road signs. iStock hide caption
Soprano Patricia Ciofi sings an aria from Verdi's Rigoletto. Bertrand Langlois/AFP/Getty Images hide caption
Seismic singing from the bottommost voices: Know your basso buffo from your basso profondo. iStock hide caption
Don't let a bounty of baritones leave you bewildered. iStock hide caption
Tenors may be characterized as head-strong and unpredictable, but they can produce pretty sounds. iStock hide caption
Don't mix up your mezzos and contraltos. iStock hide caption
From stratospheric coloraturas to jet-powered Wagnerians, learn to love our highest-flying singers. iStock hide caption
Baffled by buffo? Talking about opera can be like walking through a linguistic thicket. iStock hide caption