She’s the one who can sing, right?
That’s a little reductive, but yes, Christina Aguilera is the only member of the famous Class of ’99 (which also includes Britney Spears, 'N Sync, P!nk, Jessica Simpson, Eminem and Destiny’s Child) who has been regularly and repeatedly praised for her singing ability by people who are otherwise not noticeably interested in modern pop music. Not that we’re bitter, or anything. She’s great. At singing.

Wasn’t she a Mouseketeer?
She was indeed on the Mickey Mouse Club for a couple of years in the early '90s, at the same time as Spears and Justin Timberlake. Some people have claimed that this indicates some kind of Disney conspiracy to take over pop, but we’re more inclined to take the view that sometimes a bunch of geniuses just happen to pop up in the same place and time, like the Florentine Renaissance or Motown Records. She had to audition just like anyone else to get the chance to sing “Reflection,” the theme song to Mulan, which was her first official single.

Which led to... ?
Which led to Christina Aguilera (1999), her debut album and one of the best-selling albums of the era. In a year crowded with more great teenpop than ever before, it produced three No. 1 singles: the era-defining “Genie in a Bottle,” the downtempo “What a Girl Wants,” and the hip-hop-inflected “Come on Over Baby (All I Want Is You).” While she would rack up more critical points in the years to come, she (and just about everybody else) would never hit these commercial peaks again.

How many image changes has she had?
Like most pop stars, she’s shifted emphasis, experimented with new looks and explored new sounds in order to maintain a career with any longevity to it. After the hyper-controlled teenpop Christina Aguilera, she released Mi Reflejo, a Spanish-language album that translated some of her hits and added new songs, and a Christmas album, My Kind of Christmas, both in 2000. Mi Reflejo did well, and even won her a Latin Grammy, but she was dissatisfied with the image she was building and broke with her management to pursue a more adult-oriented, musically varied career. Stripped (2002) had her calling herself Xtina, posing almost-naked for photo shoots and generally borrowing the aesthetics of softcore porn, while the music drew more from rock and hip-hop than she had previously. Four years, a marriage, and a public kiss with Madonna later, the double album Back to Basics had her dressing up like Billie Holiday, Etta James and the Andrews Sisters (both literally and vocally), and got her the best reviews of her career from old people who like old music. Except for her Greatest Hits in 2008, that was it until 2010, when the one-two punch of Bionic and Burlesque left her sounding and looking incoherent, struggling (for the first time ever!) in a pop marketplace where Lady Gaga was the new standard of success, and Xtina’s dirrrty old weirdness wasn’t weird enough anymore.

Isn’t Aguilera a Spanish name?
Very perceptive! Yes, she was born to an Ecuadorean father and an American mother in 1980 and raised in Pennsylvania by her mother and grandparents (she still doesn’t know her father). Maybe you missed the part where we talked about her Spanish-language album? She hasn’t recorded much in Spanish since 2000, but she didn’t grow up speaking it either; the most she’s done in Spanish lately has been charity work. Which, good for her.

What’s the deal with Burlesque?
We guess she wants to be an actress? Or maybe she owes Cher money. Consensus is that it’s better than Glitter and Crossroads but worse than, uh, Showgirls—so watch at your own peril. The soundtrack is pretty bad, too, too much show and not enough pop.

What’s her best song?
This we can talk about! Although it kind of depends. Do you want the machine-tooled, slice-like-a-hammer dance-pop of “Genie in a Bottle”? The all-star funk of “Lady Marmalade” (with Pink, Lil’ Kim, and Mýa)? The raw strip-club fantasia of “Dirrty” (with Redman)? The epic vulnerability of “Beautiful”? The chopped-up soul-jazz of “Ain’t No Other Man”? We’d go on, saying the glam stomp of “Keeps Getting Better” and the screwy electro of “Not Myself Tonight,” but we’re pretty sure they’re nobody’s favorite Xtina songs.

Personal life?
She has one, yes. But like any good diva she knows how to compartmentalize and doesn’t let it spill over too much into her public life. She has a three-year-old son—as you’d know if you listened to the mushier parts of Bionic—and she’s heavily involved in various causes and charities, including world hunger, disaster relief, LGBT support and animal rights. And this is where we say jeez, Christina, leave some philanthropy for other people!