Peter Gene Hernandez (born October 8, 1985), better known by his stage name Bruno Mars, is an American singer-songwriter and record producer. Raised in Honolulu, Hawaii by a family of musicians, Mars began making music at a young age. He performed in various musical venues in his hometown throughout his childhood. He graduated from high school and then moved to Los Angeles, California to pursue a musical career. Mars produced songs for other artists, joining production team The Smeezingtons.

Mars had an unsuccessful stint with Motown Records, but then signed with Atlantic Records in 2009. He became recognized as a solo artist after lending his vocals and co-writing the hooks for the songs "Nothin' on You" by B.o.B, and "Billionaire" by Travie McCoy. He also co-wrote the hits "Right Round" by Flo Rida featuring Ke$ha, and "Wavin' Flag" by K'naan. In October 2010, he released his debut album, Doo-Wops & Hooligans. Anchored by the worldwide number-one singles "Just the Way You Are" and "Grenade", the album peaked at number three on the Billboard 200. Mars was nominated for seven Grammys at the 53rd Grammy Awards, winning Best Male Pop Vocal Performance for "Just the Way You Are".

Katheryn Elizabeth Hudson (born October 25, 1984), known by her stage name Katy Perry, is an American singer, songwriter and actress. Perry grew up with gospel music, and during her first year of high school she pursued a music career as Katy Hudson, releasing her first studio album called Katy Hudson which failed to chart. She recorded a solo album later, which was never released. After signing with Capitol Music Group in 2007, her fourth record label in seven years, she adopted the stage name Katy Perry.

She first gained recognition with the release of her first mainstream album, One of the Boys in 2008, which spawned three Billboard Hot 100 top-ten songs—"I Kissed A Girl", "Hot n Cold" and "Waking Up In Vegas". Perry supported the album with her Hello Katy Tour. In 2010, her third studio album, Teenage Dream (2010), which topped the Billboard 200 chart, and spawned five number one singles—"California Gurls", "Teenage Dream", "Firework", "E.T." and "Last Friday Night (T.G.I.F.)"—Teenage Dream was the only album (after Michael Jackson's Bad)—to do so, and the first female in history to achieve this milestone. She embarked on the California Dreams Tour, which grossed nearly $60 million worldwide. Perry re-released the album under the name of Teenage Dream: The Complete Confection on March 26, 2012, and the re-release has already spawned the number-one single "Part of Me".

Stefani Joanne Angelina Germanotta (/ˈstɛfəniː dʒʌrməˈnɑːtə/ STE-fə-nee jurr-mə-NAH-tə; born March 28, 1986), known by her stage name Lady Gaga, is an American singer and songwriter. Born and raised in New York City, she primarily studied at the Convent of the Sacred Heart and briefly attended New York University's Tisch School of the Arts before withdrawing to focus on her musical career. She began performing in the rock music scene of Manhattan's Lower East Side, and was signed with Streamline Records by the end of 2007. During her employment as a songwriter for the record company, her vocal abilities captured the attention of recording artist Akon, who signed her to his label Kon Live Distribution.

Lady Gaga came to prominence as a recording artist following the release of her debut album The Fame (2008), which was a critical and commercial success that topped charts around the world and included the international number-one singles "Just Dance" and "Poker Face". After embarking on the The Fame Ball Tour, she followed the album with The Fame Monster (2009), which spawned the worldwide hit singles "Bad Romance", "Telephone" and "Alejandro". The album's success allowed her to embark on the eighteen-month long Monster Ball Tour, which later became one of the highest-grossing concert tours of all time. Her most recent album Born This Way (2011) topped the charts of most major markets and generated more international chart-topping singles, including "Born This Way", "Judas" and "The Edge of Glory". Besides her musical career, she involves herself with humanitarian causes and LGBT activism.