Christina Maria Aguilera was born on Thursday, December 18, 1980 in Staten Island, New York, but grew up primarily in Wexford, Pennsylvania. She is colloquially known as Xtina. .

Christina Aguilera grew up primarily in Wexford, Pennsylvania (just outside Pittsburgh, Pennsylvania), after living in various places around the world. Her father, Fausto Aguilera, is a U.S. Army sergeant of Ecuadorian descent, and her mother, Shelly Loraine Fidler (now known as Shelly Kearns), is a Spanish translator from Newfoundland , Canada , and of remote Irish descent. Christina's parents met while Fausto was serving at Earnest Harmon Air Force Base in Stephenville, Newfoundland and Labrador.

As a child she performed at block parties and in talent competitions-defeating opponents with little effort. Christina soon gained media attention, and was known to some as "the little girl with the big voice". Since Christina was able to talk, she set a goal to become a professional singer.

On March 15 , 1990 , she appeared on Star Search singing Ella Fitzgerald 's Sunday Kind Of Love , but failed to win. Soon after losing on Star Search , she appeared on KDKA-TV local access show Wake Up With Larry Richert to perform the same song again. Later on, she would sing "Vision Of Love", Mariah Carey 's first single, and astonished everybody in attendance by hitting every riff and note, including Carey's trademark whistle register note. People remarked that the then-ten year old "sounded twenty".

As a teenager, Christina sang the National Anthem " The Star-Spangled Banner " before Pittsburgh Steelers football and Pittsburgh Pirates baseball games. In 1988, she appeared on Star Search but she didn't win. Her breakthrough came in 1993 when she joined the Disney Channel 's variety show "The New Mickey Mouse Club." Her co-stars included Britney Spears, Justin Timberlake and JC Chasez, who went on to join NSYNC, and Keri Russell, who later become the star of Felicity.

Christina’s first song "All I Wanna Do" was a collaborative with Japanese pop sensation Keizo Nakanishi was recorded in Japan, but she only caught the attention of Americans when she released the song "Reflection" for the Disney animated production of Mulan in 1998. The video clip featured a young Christina with a bob hair cut. The song prompted RCA to sign her up. So far she has achieved four #1 singles on the Billboard Hot 100 chart, as well as two top five albums and four Grammy Awards in the United States .

In 1997 , Aguilera competed in an international singing contest at the Golden Stag Festival in Transylvania, Romania , where she shared the stage with Sheryl Crow and Diana Ross . In 1998 , after proving herself as a whistle register singer, singing the High "E" note above middle "C" during audition, she was selected to perform the song "Reflection" for the Disney animated production of Mulan ( 1998 ). The music video promoting the film featured a young Aguilera with bobbed hair. It was her first music video. "Reflection" peaked at number #15 on the Adult Contemporary Singles Chart. The song was nominated for a Golden Globe Award for Best Original Song for a Motion Picture in 1998.

Her self-titled album was released in 1999 and reached the top of the Billboard 200 and Canadian album charts selling eight million albums in the United States. "Genie in a Bottle", "What a Girl Wants" and "Come On Over Baby (All I Want Is You)" all reached the top of the Billboard Hot 100 in 1999 and 2000 and "I Turn to You" went top 5 in the US.

Christina beats Britney Spears at the Grammy Awards of 2000 to win the "Grammy Award for Best New Artist". That year she released her first Latin album, “Mi Reflejo.” At this time she claimed to have been learning Spanish. This album was a version of her debut album in Spanish and reached number 27 on the Billboard 200 and number one on the Latin album charts. The single "Falsas Esperanzas" from the album reached the top 40 in Argentina in 2001. Ricky Martin asked her to a duet with him on "Nobody Wants To Be Lonely" on his Sound Loaded album released in late 2000. The song was released as the second single in 2001 going top 5 in the UK, top 10 in the US and top 40 in Canada, Switzerland and Australia.

The move towards a raunchier image was shown in her appearance in the video for "Lady Marmalade" which showed her, Lil Kim, Pink and Mya dressed in lingerie. The track was produced by Timbaland and Missy Elliott and appeared on the soundtrack for the Baz Luhrmann film Moulin Rouge! The song which is a remake of the 1975 hit by LaBelle, went to number one on the Billboard Hot 100 and won a Grammy Award for Best Pop Collaboration with Vocals. The song also topped in Australia with the Moulin Rouge! soundtrack being the best selling album of 2001 in that country.

Her second official English-language album was “Stripped.” This features many interludes, one before the track "Infatuation", which features her speaking Spanish, and a duet with Alicia Keys; however, Aguilera cannot speak Spanish fluently yet - even though she is learning Spanish - as she forgot the language while growing up. By the year 2002, however, her previously heralded vocals were much overlooked as she began to change her fresh, youthful image into that of a highly sexualized woman with hip-hop and porn-star influences. After the release of that album, she has taken part in photo shoots for the magazines Maxim, Rolling Stone, and Cosmo Girl. Many of these photographs featured her nude or semi-nude. At the same time, Aguilera began to project a more sexually provocative image in order to compete with Britney Spears. She denied that this change was a matter of publicity, claiming that the erotic emphasis better reflected her true personality than did the image she projected in 1999. She told German paper Netzeitung, "I like having sex. It's fun....I love experimenting with my sexuality. I want to try out as much as possible. It would be wrong of me to hide this side of my personality. I have fun being sexy and tough at the same time."

The video for her 2002 single "Dirrty" featured her writhing with members of both sexes including a female-only shower scene in which she was wearing only a thong and a bra. As she puts it, "I like the way I am. This is how I bring out my sexuality."

The "Dirrty" video also made the news when the government of Thailand banned the video from national television, because the posters that appear in the background of the boxing ring advertise, in the Thai language, the sex tourism and underage girls of Thailand. The producers and director of the video claimed to be ignorant of the meaning of the posters. She is currently banned from entering Thailand as it is considered to have offended the Thai people.

Musical peers such as Shakira, Jessica Simpson, and Kelly Osbourne criticized the video, but Aguilera responded by pointing out, "I may have been the naked-ass girl in the video, but if you look at it carefully, I'm also at the forefront. I'm not just some lame chick in a rap video; I'm in the power position, in complete command of everything around me. To be totally balls-out like that is, for me, the measure of a true artist."

Ironically, the new raunchy image seems to have negatively affected the sales of the album at least in the US when released in late 2002. While the album debuted at number 2 on the UK album charts and number 3 in Canada, it made a low entry given the success of her debut album. However, the success of subsequent singles off the album meant that Stripped reached a peak of number 2 on the Billboard 200 in 2004. The staying power of the album was also shown in the UK when the album was consistently in the top 20 of the album charts between late 2002 and early 2004. The album is quadruple platinum in Australia despite only reaching a peak of number 7 - again a reflection of its consistency between late 2002 and 2004.

There have been a number of hit singles from Stripped including:

"Dirrty", the first single featuring rapper Redman went to number one in the UK, Ireland and was a top ten hit in the Netherlands, Spain and Australia - it only reached number 48 on the Billboard Hot100 reflecting the early sales backlash;
"Beautiful" went to number 1 in the UK, Ireland, Australia and Canada as well as the US top 40 and adult contemporary charts - it reached number 2 on the Billboard Hot 100;
"Fighter" went to number 20 in the US and reached top 5 on world airplay charts performing well in countries such as Canada, Australia and Argentina;
"Can't Hold Us Down" another collaboration with Lil Kim was another top 5 hits on world airplay charts and reached number 12 on the Billboard Hot 100; and
"The Voice Within" was another strong track on worldwide radio becoming the second most played track on European radio in early 2004 and reached number 33 on the Billboard Hot 100.
"Beautiful" earned Christina Aguilera the Grammy Award for Best Female Pop Vocal Performance at the Grammy Awards of 2004. The Gay & Lesbian Alliance Against Defamation (GLAAD) presented a special award for inclusion to her in February 2003 for the positive images of gay and transgender people.

Aguilera went so far as to condemn her work on her first album, telling an interviewer, "I was playing a part dictated by my then manager and my record company. I hated who I was back then..." The Stripped album contains a number of songs based on personal development themes including "Beautiful", "Fighter" and "I'm OK".

In early 2003 Aguilera aroused much comment when she gained a noticeable amount of weight. Aguilera was quoted as saying, "I couldn't care less about stupid diets. Eating is sensual and fun. I'm not going to let it be spoiled by calorie counting." Whether she will be able to reconcile this attitude to her sexually-charged image remains to be seen.

In June 2003, she began a tour with Justin Timberlake, called the "Justified & Stripped" tour. In the fall of that year, she toured Germany. During the tour she dyed her hair black.

Aguilera opened up a new vein of controversy in Autumn 2003 by viciously attacking fellow teen-pop musicians. She told Blender magazine, "Look at people like Beyoncé or Britney. They're desperate to come across as sweet, good little girls, but then you see them in photo shoots that are extremely sexual—tight little booty shorts, and not much else. So why do they try to be virginal in interviews?" Concerning her most formidable rival, Britney Spears, she claimed, "These people aren't artists; they're just performers—fake and superficial...I was up for kissing Britney, but Britney wasn't. She was....she seemed very distant, even during rehearsals. Every time I tired to start a conversation with her—well, let's just say she seemed nervous the whole time. I wanted to reach out to her, because I feel she needs somebody in her life right now to help guide her."

Some people believe that Christina Aguilera is actually Dee Snider (the lead singer of the Twisted Sister) trying to revive his dead career as a rock singer.