Ariana Grande then: Frazer Harrison / Getty Images A Nickelodeon TV star (starring on Victorious). Ariana Grande now: Ariana Grande / instagram.com Queen of Ponytails, Bops, Not Enunciating, and Breaking Eras. Rihanna then: Larry Busacca / Getty Images Released maybe her best album ever, Rated R. Rihanna now: Martin Bureau / AFP / Getty Images Queen of Giving Zero Fucks, actor, singer of bops, fashion icon, literally reinvented the beauty industry as a makeup mogul, and head of a high-end fashion brand. Jennifer Lopez then: Jason Merritt / Getty Images A multi-hyphenate star: singer, actor, dancer, and designer. Jennifer Lopez now: Taylor Hill / FilmMagic A multi-hyphenate star: singer, actor, dancer, designer, and TV producer who is celebrating 20 years of being a pop diva. Selena Gomez then: Tiffany Rose / WireImage A Disney Channel star who was about to release her debut album, Kiss & Tell (with the Scene). Selena Gomez now: Theo Wargo / Getty Images Finally getting close to releasing her new album (her first in four years!). Taylor Swift then: Jeff Kravitz / FilmMagic Ruled both the country and pop charts with songs off her second album, Fearless. Taylor Swift now: Steve Granitz / WireImage Releasing her seventh studio album this summer. Janet Jackson then: Vittorio Zunino Celotto / Getty Images A living legend. Janet Jackson now: Nicholas Hunt / WireImage A living legend who was finally inducted into the Rock & Roll Hall of Fame (an honor she deserved a decade ago). Christina Aguilera then: Jason Merritt / Getty Images Was quietly working on her way-ahead-of-its-time album Bionic. Christina Aguilera now: Bravo / Getty Images Currently doing her The Xperience residency in Las Vegas. Gwen Stefani then: Michael Buckner / Getty Images An accomplished singer, songwriter, designer, and one part of alt-rock's favorite couple. Gwen Stefani now: Karwai Tang / WireImage Accomplished singer, songwriter, designer, and one part of your mom's favorite couple. Demi Lovato then: Kristian Dowling / Getty Images A Disney star who had just released her second album, Here We Go Again. Demi Lovato now: Demi Lovato/ instagram.com An advocate for mental health, who has been very vocal and honest about her own personal struggles and addictions. Also, still a friggin' talented vocalist. Madonna then: Jon Kopaloff / FilmMagic Was busy wrapping up the European leg of her Sticky & Sweet Tour. Also released her third greatest-hits album, Celebration. Madonna now: Kevin Mazur / Getty Images Just released her 14th album, Madame X. Adele then: Paul Bergen / Redferns Rising British star who took home the Grammys for Best New Artist and Best Female Pop Vocal Performance. Adele now: Adele/ instagram.com A legend and Queen of the Breakup Songs, who just teased us with the news that her new album, 30, is coming soon. Alicia Keys then: Bennett Raglin / WireImage Was getting ready to release her fourth album, The Element of Freedom. Alicia Keys now: Dia Dipasupil / FilmMagic Spinning her chair as a judge on The Voice. Kylie Minogue then: Kristian Dowling / Getty Images Embarked on her first-ever North American tour. Kylie Minogue now: Mike Marsland / Mike Marsland / WireImage A legend — that the US is still sleeping on — who is about to release her greatest hits album Step Back in Time: The Definitive Collection. Katy Perry then: Jason Merritt / Getty Images Embarked on her first headlining tour — the Hello Katy Tour — to promote One of the Boys. Katy Perry now: Lester Cohen / Getty Images Just released her latest single "Never Really Over" and officially ended her feud with Taylor Swift. Mariah Carey then: Jason Merritt / Getty Images Gave a wonderful performance as a social worker in Precious and dropped her 12th studio album, Memoirs of an Imperfect Angel. Mariah Carey now: Ethan Miller / Getty Images Queen of Memes and also something that rhymes with "schminny schmegend." Miley Cyrus then: Miguel Villagran / Getty Images Just starred in Hannah Montana: The Movie. Miley Cyrus now: Neilson Barnard / Getty Images Just released her EP, She Is Coming. Beyoncé then: Kevin Winter / Getty Images Embarked on her I Am... World Tour in support of her album I Am... Sasha Fierce. Beyoncé now: View this photo on Instagram Instagram: @undefined Literally has us all in suspense as we wait for her new song to drop from The Lion King soundtrack (aka Beyoncé's The Lion King). Lady Gaga then: Kevin Mazur / WireImage Released one of the greatest pop albums of all time: The Fame Monster. Lady Gaga now: Karwai Tang / Getty Images An Oscar winner who is preparing us all for #LG6. Britney Spears then: Frazer Harrison / Getty Images Embarked on her Circus Tour in support of her album Circus. Britney Spears now: Britney Spears/ instagram.com A living legend, who happens to be the Queen of Instagram Posts, sayer of "cool," and owner of lots of mini furniture. A bestselling artist, a painter, (private) runway model, workout video queen, and SKINNY. AS. A. NEEDLE.