Stefani Joanne Angelina Germanotta (born March 28, 1986), better known by her stage name Lady Gaga, is an American pop singer-songwriter. She began performing in the rock music scene of New York City's Lower East Side in 2003 and enrolled at New York University's Tisch School of the Arts. She soon signed with Streamline Records, an imprint of Interscope Records. During her early time at Interscope, she worked as a songwriter for fellow label artists and captured the attention of Akon, who recognized her vocal abilities, and signed her to his own label, Kon Live Distribution.

Gaga came to prominence following the release of her debut studio album The Fame (2008), which was a commercial success and achieved international popularity with the singles "Just Dance" and "Poker Face". The album reached number one on the record charts of six countries, accomplished positions within the top-ten worldwide, and topped the Billboard Dance/Electronic Albums chart while simultaneously peaking at number two on the Billboard 200 chart in the United States. Achieving similar worldwide success, the follow-up EP The Fame Monster (2009), produced a further two global chart-topping singles "Bad Romance" and "Telephone" and allowed her to embark on a second global headlining concert tour, The Monster Ball Tour, just months after having finished her first, The Fame Ball Tour. Her second studio album, Born This Way, is scheduled for release in 2011.

Inspired by glam rock artists like David Bowie and Queen, as well as pop singers such as Madonna and Michael Jackson, Gaga is well-recognized for her outré sense of style as a recording artist, in fashion, in performance and in her music videos. Her contributions to the music industry have garnered her numerous achievements including two Grammy Awards, amongst twelve nominations; two Guinness World Records; and the estimated sale of fifteen million albums and fifty-one million singles worldwide. Billboard named her as the Artist of the Year in 2010 and ranked her as the 73rd Artist of the 2000s decade. Gaga has been included in Time magazine's annual Time 100 list of the most influential people in the world as well as Forbes' list of the 100 Most Powerful and Influential celebrities in the world. Forbes also placed her at number seven on their annual list of the World's 100 Most Powerful Women.

Lady Gaga was born Stefani Joanne Angelina Germanotta in New York City on March 28, 1986, the eldest child of Joseph Germanotta, an internet entrepreneur, and Cynthia (née Bissett). She learned to play piano from the age of four, went on to write her first piano ballad at 13 and began performing at open mike nights by age 14. Gaga was raised a Roman Catholic. At the age of 11, Gaga attended Convent of the Sacred Heart, a private all-girls Roman Catholic school on Manhattan's Upper East Side, but has stressed that she does not come from a wealthy background, saying that her parents "both came from lower-class families, so we've worked for everything – my mother worked eight to eight out of the house, in telecommunications, and so did my father."

An avid thespian in high school musicals, Gaga portrayed lead roles as Adelaide in Guys and Dolls and Philia in A Funny Thing Happened on the Way to the Forum. She described her academic life in high school as "very dedicated, very studious, very disciplined" but also "a bit insecure" as she told in an interview, "I used to get made fun of for being either too provocative or too eccentric, so I started to tone it down. I didn’t fit in, and I felt like a freak." Acquaintances dispute that she did not fit in school. "She had a core group of friends; she was a good student. She liked boys a lot, but singing was No. 1," recalled a former high school classmate. Referring to her "expressive, free spirit", Gaga told Elle magazine "I'm left-handed!"

At age 17, Gaga gained early admission to the New York University's Tisch School of the Arts and lived in a NYU dorm on 11th Street. There she studied music and improved her songwriting skills by composing essays and analytical papers focusing on topics such as art, religion, social issues and politics. Gaga felt that she was more creative than some of her classmates. "Once you learn how to think about art, you can teach yourself," she said. By the second semester of her sophomore year, she withdrew from the school to focus on her musical career. Her father agreed to pay her rent for a year, on the condition that she re-enroll for Tisch if she was unsuccessful. "I left my entire family, got the cheapest apartment I could find, and ate shit until somebody would listen," she said.

Gaga had initially signed with Def Jam Recordings at the age of 19, although she was dropped by the label after only three months. Shortly after, her former management company introduced her to songwriter and producer RedOne, whom they also managed. The first song she produced with RedOne was "Boys Boys Boys", a mash-up inspired by Mötley Crüe's "Girls, Girls, Girls" and AC/DC's "T.N.T." She moved into an apartment on the Lower East Side and recorded a couple of songs with hip-hop singer Grandmaster Melle Mel for an audio book accompanying the children's book The Portal in the Park by Cricket Casey. She also started the Stefani Germanotta Band with some friends from NYU. They recorded an extended play of their ballads at a studio underneath a liquor store in New Jersey, becoming a local fixture at the downtown Lower East Side club scene. She began experimenting with drugs soon after, while performing at neo-burlesque shows. Her father did not understand the reason behind her drug intake and could not look at her for several months.

She was known thereafter as Lady Gaga. The New York Post, however, has reported that this story is incorrect, and that the name resulted from a marketing meeting. Throughout 2007, Gaga collaborated with performance artist Lady Starlight, who helped create her on-stage fashions. The pair began playing gigs at downtown club venues like the Mercury Lounge, The Bitter End, and the Rockwood Music Hall, with their live performance art piece known as "Lady Gaga and the Starlight Revue." Billed as "The Ultimate Pop Burlesque Rockshow", their act was a low-fi tribute to 1970s variety acts. In August 2007, Gaga and Starlight were invited to play at the American Lollapalooza music festival. The show was critically acclaimed, and their performance received positive reviews. Having initially focused on avant-garde electronic dance music, Gaga found her musical niche when she began to incorporate pop melodies and the glam rock of David Bowie and Queen into her music.

Gaga's second studio album and third major release Born This Way, whose title was announced during her acceptance speech for Video of the Year at the 2010 MTV Video Music Awards, will be released on May 23, 2011. Its arrival will follow the release of its lead single on February 13, 2011. These dates were tweeted by Gaga at the stroke of midnight on New Year's Day, 2011. Described as "a marriage of electronic music with major ] metal or rock 'n' roll, pop, anthemic style melodies with really sledge-hammering dance beats", Born This Way will be Gaga's third release in three years. She stated, "It came so quickly. I've been working on the album for months, and I feel very strongly that it's finished right now. Some artists take years. I don't. I write music every day." With two tracks already confirmed by Gaga – one she has been performing during The Monster Ball Tour, she has referred to the album as "the greatest" of the decade about "what keeps us up at night and what makes us afraid." Likening Born This Way to "bad kids going to church" that are "having fun on a high level", Gaga characterized her new music as "something so much deeper than a wig or lipstick or a fucking meat dress" and upon hearing it, Akon remarked that she will take music to the "next level."

Lending her vocal talent elsewhere, Gaga also paired with Elton John to record an original duet for the soundtrack to the forthcoming animated feature film Gnomeo and Juliet. The song, titled "Hello, Hello", is scheduled for release in February 2011.

Musical style and influences
Gaga has been influenced by glam rock artists such as David Bowie and Queen, as well as pop music artists such as Madonna, Britney Spears and Michael Jackson. The Queen song "Radio Ga Ga" inspired her stage name, "Lady Gaga". She commented: "I adored Freddie Mercury and Queen had a hit called 'Radio Gaga'. That's why I love the name. Freddie was unique – one of the biggest personalities in the whole of pop music." In response to the comparisons between herself and Madonna, Gaga stated: "I don't want to sound presumptuous, but I've made it my goal to revolutionise pop music. The last revolution was launched by Madonna 25 years ago." Actress and singer Grace Jones was also cited as an inspiration, along with Blondie singer Debbie Harry.

Gaga's vocals have drawn frequent comparison to those of Madonna and Gwen Stefani, while the structure of her music is said to echo classic 1980s pop and 1990s Europop. While reviewing her debut album The Fame, The Sunday Times asserted "in combining music, fashion, art and technology, Lady GaGa evokes Madonna, Gwen Stefani circa 'Hollaback Girl', Kylie Minogue 2001 or Grace Jones right now." Similarly, The Boston Globe critic Sarah Rodman commented that she draws "obvious inspirations from Madonna to Gwen Stefani... in  girlish but sturdy pipes and bubbly beats." Though her lyrics are said to lack intellectual stimulation, " does manage to get you moving and grooving at an almost effortless pace." Music critic Simon Reynolds wrote that "Everything about Gaga came from electroclash, except the music, which wasn't particularly 1980s, just ruthlessly catchy naughties pop glazed with Auto-Tune and undergirded with R&B-ish beats.