Saturday Night Live (SNL) is a late-night sketch comedy and variety show created by Lorne Michaels. It premiered on NBC, a terrestrial television network, on October 11, 1975 under the title NBC's Saturday Night. The show often satirizes contemporary American popular culture and politics. Saturday Night Live features a two-tiered cast: the repertory members, also known as the "Not Ready for Prime-Time Players," and newer cast members, known as "Featured Players." Each week, the show features a host, often a well-known celebrity, who delivers an opening monologue and performs in sketches with the cast. A musical guest is also invited to perform several sets (usually two, and occasionally more). Every so often a host or musical guest will fill both roles, such as was the case with Britney Spears in 2000 and 2002, Jennifer Lopez in 2001 and 2010, Justin Timberlake in 2003, 2006 and 2013, Taylor Swift in 2009, Bruno Mars in 2012,  Lady Gaga in 2013, Drake in 2014, and Blake Shelton and Miley Cyrus in 2013 and 2015. With the exception of Season 7 and several other rare cases, the show has begun with a cold open that ends with someone breaking character and proclaiming "Live from New York, it's Saturday Night!"