Britney Jean Spears (born December 2, 1981) is an American singer, actress, and dancer. Often referred to as the "Princess of Pop", she is credited with influencing the revival of teen pop during the late 1990s and early 2000s. After appearing in stage productions and television series, Spears signed with Jive Records in 1997 at age fifteen. Her first two studio albums, ...Baby One More Time (1999) and Oops!... I Did It Again (2000), are among the best-selling albums of all time and made Spears the best-selling teenage artist of all time. With first-week sales of over 1.3 million copies, Oops!... I Did It Again held the record for the fastest-selling album by a female artist in the United States for fifteen years. Spears adopted a more mature and provocative style for her albums Britney (2001) and In the Zone (2003), and starred in the 2002 film Crossroads.

Spears was executive producer of her fifth studio album Blackout (2007), often referred to as her best work. Following a series of highly publicized personal problems, promotion for the album was limited, and Spears was involuntarily placed in a conservatorship. Since then, she released the chart-topping albums, Circus (2008) and Femme Fatale (2011), the latter of which became her most successful era of singles in the US charts. She embarked on a four-year concert residency, Britney: Piece of Me, at Planet Hollywood Resort & Casino in Las Vegas to promote her next two albums Britney Jean (2013) and Glory (2016). In 2019, Spears's legal battle over her conservatorship became more publicized and led to the establishment of the #FreeBritney movement. In 2021, the conservatorship was terminated following her public testimony in which she accused her management team and family of abuse.

Regarded as a pop icon, Spears has sold over 100 million records worldwide, including over 70 million in the United States, making her one of the world's best-selling music artists. She has achieved six number-one albums on the Billboard 200 and four number-one singles on the US Billboard Hot 100: "...Baby One More Time", "Womanizer", "3", and "Hold It Against Me". The "S&M" remix also topped the Billboard chart. Her singles "Oops!... I Did It Again", "Toxic", and "Scream & Shout" topped the charts in most countries. With "3" in 2009 and "Hold It Against Me" in 2011, Spears became the second artist after Mariah Carey in the Hot 100's history to debut at number one with two or more songs. Her heavily choreographed videos earned her the Michael Jackson Video Vanguard Award. She has earned numerous other awards and accolades, including a Grammy Award, 15 Guinness World Records, six MTV Video Music Awards, seven Billboard Music Awards (including the Millennium Award), the inaugural Radio Disney Icon Award, and a star on the Hollywood Walk of Fame.

Spears was ranked by Billboard as the eighth-biggest artist of the 2000s. In the United States, she is the fourth best-selling female album artist of the Nielsen SoundScan era as well as the best-selling female album artist of the 2000s. "...Baby One More Time" was named the greatest debut single of all time by Rolling Stone in 2020. In 2004, Spears launched a perfume brand with Elizabeth Arden, Inc.; sales exceeded $1.5 billion as of 2012. Forbes has reported Spears as the highest-earning female musician of 2001 and 2012. By 2012, she had topped Yahoo!'s list of most searched celebrities seven times in twelve years. Time named Spears one of the 100 most influential people in the world in 2021, while also winning the reader poll by receiving the highest number of votes.