1-2-3, 1, 2, 3 or One, Two, Three may refer to:

Britney Jean Spears (born December 2, 1981) is an American recording artist and entertainer. Born in McComb, Mississippi, and raised in Kentwood, Louisiana, Spears began performing as a child, landing acting roles in stage productions and television shows. She signed with Jive Records in 1997 and released her debut album ...Baby One More Time in 1999, which became the best-selling album by a teenage solo artist. During her first decade in the music industry, she became a prominent figure in mainstream popular music and popular culture, followed by a much-publicized personal life. Her first two albums established her as a pop icon and broke sales records, while title tracks "...Baby One More Time" and "Oops!... I Did It Again" became international number-one hits. Spears was credited with influencing the revival of teen pop during the late 1990s, and became the 'best-selling teen aged artist of all time' before she turned 20, garnering her the honorific title of "Princess of Pop".

Len Barry (born Leonard Borisoff, June 12, 1942, West Philadelphia, Pennsylvania, United States) is a retired American vocalist, songwriter and record producer.

Born and raised in Philadelphia, Barry had little thought of a show business career while still in school. Instead, he aspired to become a professional baseball player upon his graduation. It was not until he entered military service and had occasion to sing with the U.S. Coast Guard band at Cape May, NJ, and was so encouraged by the response of his military audiences, that he decided to make music a career.

Upon his discharge from military service, Barry returned home to Philadelphia and joined The Dovells as their lead singer. His is the lead voice on their best selling records "Bristol Stomp", "Hully Gully Baby" and "You Can't Sit Down", among others. "Bristol Stomp" sold over one million copies, and was awarded a gold disc. Barry also made film appearances with The Dovells in films such as Don't Knock the Twist, as well as guest appearances on US television on The Dick Clark Show, Shindig, and Hullabaloo. Soon after leaving the group, Barry recorded his first solo single "Lip Sync".

Gloria María Milagrosa Fajardo García de Estefan, known professionally as Gloria Estefan (born September 1, 1957) is a Cuban-born American singer, songwriter, actress and entrepreneur. Known as the "Queen Of Latin Pop", she is in the top 100 best selling music artists with over 100 million albums sold worldwide, 31.5 million of those in the United States alone. She has won three Grammy Awards, and 4 Latin Grammys, and is the most successful crossover performer in Latin music to date.

Gloria María Milagrosa Fajardo was born September 1, 1957 in Havana, Cuba, to Jose and Gloria Fajardo. Her maternal grandfather, Leonardo Garcia, immigrated to Cuba from Pola de Siero, Asturias, Spain, where he married Gloria's maternal grandmother, originally from Logroño, Spain. Prior to the Cuban Revolution, her father was a Cuban soldier and a bodyguard to Cuban dictator Fulgencio Batista. The Fajardo family fled to Miami, Florida as a result of the Cuban Revolution and settled down there. Shortly after they moved to the United States, Gloria's father joined the US military and fought in the Vietnam War and moved to Houston, Texas, also having participated in the failed Bay of Pigs Invasion. Gloria attended St. Michael-Archangel School and Our Lady of Lourdes Academy in Miami. Her father became ill after returning from Vietnam and Gloria helped her mother, Gloria Fajardo, care for him. Her mother worked as a school teacher for the Dade County Public School system. Gloria Estefan graduated from college in 1979 with a B.A. in psychology, with a minor in French, from the University of Miami. When she was studying at the university, she worked as an English/Spanish/French translator at Miami International Airport Customs Department and, because of her language abilities, was once approached by the CIA as a possible employee. Estefan was raised Catholic.

Alexander Marcus (born 26 July 1972 in Berlin) is a persona of the German music producer Felix Rennefeld. He has become popular throughout Germany after a series of videos he produced and displayed on YouTube.

After his parents were divorced Alexander Marcus lived with his grandmother in the country, where he took part in the popular children's dance group "Edelweißchen". At eighteen he went to the US and lived in New York and Miami, and while there experienced international and electronic music. It was here that he formed the idea to mix the two music styles. He has been living in Berlin since 2005. On 6 June 2008 he released his debut album Electro Lore with Kontor Records, which included guest contributions by Manny Marc and Frauenarzt.

Rennefeld's music is a mixture of modern electronic club music and folk music, which he has named 'Electro Lore', a combination of 'electro' and 'folklore'. Alexander Marcus exaggerates many of the clichés present in pop music, and his music videos feature "trashy" objects, such as a recurrent plastic globe called "Globi". Spiegel Online sees the character as a typical example of a return to pop-art social criticism. Never breaking out of character, he leaves the question of whether he is a parody unanswered: