“Perry’s commercial breakthrough came once she released her first mainstream studio album One of the Boys (2008). This was preceded by the release of her first single “I Kissed a Girl”. Several successful singles followed, including “Hot n Cold”, “Thinking of You” and “Waking Up in Vegas”. Perry embarked on the Hello Katy Tour in support of the album. She followed this up with her second studio effort Teenage Dream which was an instant commercial success, topping the album charts in several countries. It spawned five number-one hits on the BillboardHot 100—”California Gurls”, “Teenage Dream”, “Firework”, “E.T.” and “Last Friday Night (T.G.I.F.)”. It became the first album in history recorded by a female artist to achieve this, and the second after Michael Jackson’s Bad (1987). In support of the album, she embarked on the California Dreams Tour. Teenage Dream was followed by a re-release entitled The Complete Confection that spawned an additional number one, “Part of Me”.