From left, Niall Horan, Zayn Malik, Liam Payne, Louis Tomlinson, and Harry Styles of musical group One Direction, accepted the award for favorite pop/rock album for "Take Me Home" at the American Music Awards at the Nokia Theatre in Los Angeles on Sunday, Nov. 24, 2013.
Singer Jennifer Lopez performed during the awards.
Rihanna accepted the Icon Award from her mother Monica Fenty, who praised her daughter's positive attitude in the face of challenges.
Macklemore, right, and Ryan Lewis accepted the award for favorite rap/hip-hop album for "The Heist" via satellite from Miami. Macklemore used the fact that the two were in Florida to encourage viewers to fight against racial profiling, specifically mentioning the 2012 shooting of Trayvon Martin in Sanford, Fla.
Justin Timberlake won multiple awards, including favorite male pop/rock artist, favorite male soul and R&B artist, and favorite soul and R&B album for "The 20/20 Experience."
Awards show host Pitbull performed his song "Timber" with Ke$ha, left.
Tyler Hubbard and Brian Kelley of Florida Georgia Line performed "Ride Wit Me" with Nelly at the awards.
The band Imagine Dragons performed a medley at the awards. The band won the alternative artist award.
Small but mighty, singer Ariana Grande performed a medley of songs at the AMAs, then later won new artist of the year -- charming the audience with a speed-reading of her "thank you" list while accepting the prize.
Justin Timberlake picked up the first award of the evening, accepting the favorite pop/rock male artist prize. He thanked his fans for making it all happen.
Katy Perry, dressed in full geisha outfit, sang her song "Unconditionally" to kick off the AMAs.
Miley Cyrus played off her recent controversial image by wearing an outfit decked out with kittens and performing in front of a huge image of one.
Musician Ian Axel of A Great Big World and singer Christina Aguilera perform during the awards.
Brian Kelly and Tyler Hubbard of Florida Georgia Line strutted on the red carpet at the AMAs. Later on the show they sang "Cruise," then were joined by Nelly for "Ride Wit Me."
Taylor Swift went sheer and sparkly at the AMAs on the red carpet. Later on she earned an award for best country album for "Red," and said her fans were "everything" to her.
Lady Gaga kicked off the AMAs with a bang, or rather, a whinny: She was carried down the red carpet astride a fake white horse piloted by two people and led by a third. She told E!'s Giuliana Rancic that it was meant to be reminiscent of "Bianca Jagger arriving at Studio 54 on her white horse."
N'Sync member and TV personality Lance Bass helped get the party started at the AMAs by hosting the live-streamed red carpet preshow.
Agent provocateur Miley Cyrus was her usual enthusiastic self on the red carpet at the awards, but took a slightly toned-down look with a white suit (though complete with plunging jacket neckline).
Musician James Durbin and his wife Heidi Lowe were armed and extremely adorable on the red carpet at the AMAs.
Katy Perry arrived at the AMAs in a sweeping strapless black dress festooned with flowers and dots, but by the time she opened the show she'd changed into full geisha gear to perform "Unconditionally."
"Thor" actress Jaimie Alexander strolled the red carpet in a dark, but shiny, criss-cross look.
Zayn Malik, Louis Tomlinson, Liam Payne, Harry Styles and Niall Horan, aka One Direction, gathered on the red carpet at the AMAs prior to their performance of "Story of My Life" live on the show.
"American Horror Story" actress Emma Roberts waved at photographers and fans on the red carpet ahead of the awards in a shiny, foil-like dress; she also introduced One Direction as her favorite band.
Marc Anthony left his fancy duds at home and attended the AMAs in plaid and denim, and after walking the red carpet presented the Soul/R&B Female Artist award with Zoe Saldana to Rihanna. He also won the award for favorite Latin Music artist.