Ariana Grande

Ariana Grande-Butera (born June 26, 1993), known professionally as Ariana Grande (/ˌɑːriːˈɑːnə ˈɡrɑːndeɪ/), is an American singer and actress. She began her career in the Broadway musical 13, before landing the role of Cat Valentine on the Nickelodeon television series Victorious in 2009. After four seasons, the show ended, and Grande starred on the spinoff, Sam & Cat, which ended in 2014. She has also appeared in other theatre, television and film roles and lent her voice to animated television and films.

Grande's music career began with the soundtrack Music from Victorious (2011). She signed a recording contract with Republic Records and released her debut studio album Yours Truly in 2013, which debuted at number one on the US Billboard 200. The album's lead single, "The Way", reached the top-ten of the Billboard Hot 100, with critics comparing her wide vocal range to Mariah Carey's.

Grande's second studio album, My Everything (2014), also reached number one in the United States and charted well in various other countries. With the singles "Problem", "Break Free", "Bang Bang" and "Love Me Harder" from that album, she spent 34 continuous weeks in the top 10 of the Billboard Hot 100 and had the most top 10 singles of any artist in 2014. In 2015, Grande promoted My Everything with her first world tour, The Honeymoon Tour, and guest-starred in the Fox comedy-horror TV series Scream Queens. She also released the lead single "Focus" from her upcoming third album, released a holiday EP album, Christmas & Chill, and was heard on several collaborative projects.

Justin Bieber

Justin Drew Bieber (/ˈbiːbər/; born March 1, 1994) is a Canadian singer, songwriter, and record producer. Bieber released his debut EP, My World, in late 2009. It was certified platinum in the U.S. He became the first artist to have seven songs from a debut record chart on the Billboard Hot 100. Bieber released his first full-length studio album, My World 2.0, in 2010. It debuted at or near number one in several countries and was certified triple platinum in the U.S. It was preceded by his most successful single to date, "Baby".

Following his debut album, he had his first headlining tour, the My World Tour, released the remix albums My Worlds Acoustic and Never Say Never – The Remixes -- and the 3D biopic-concert film Justin Bieber: Never Say Never. He released his second studio album, Under the Mistletoe, in November 2011, when it debuted at number one on the Billboard 200. Bieber released his third studio album, Believe, in 2012. His fourth studio album Purpose was released in November 2015. His U.S. album and singles sales total 44.7 million.