Kesha is an American singer, songwriter, and rapper. In 2005, at age 18, Kesha was signed to producer Dr. Luke's label Kemosabe Records. Her breakthrough came in early 2009 after appearing on American rapper Flo Rida's number-one single "Right Round". Her debut album, Animal, and her first extended play, Cannibal, were released in 2010. Kesha's music and image propelled her to immediate commercial success, with Animal debuting as the number-one album in the United States. She also achieved two number-one singles, "Tik Tok" and "We R Who We R", and a string of top-ten singles from the album and its re-release. At the same time, she continued to write songs for other artists, including "Till the World Ends" for Britney Spears. Warrior, her second studio album, was released in December 2012, spawning Kesha's eighth top-ten single with "Die Young", and her ninth and tenth Top 40 hits with "C'Mon" and "Crazy Kids". "Tik Tok" is among the best-selling digital singles in history, selling over 14 million units internationally.