William Henry Cosby Jr. ( KOZ-bee; born July 12, 1937) is an American comedian, actor, and media personality. He has made significant contributions to American and African-American culture, and gained a reputation as "America's Dad" for his portrayal of Cliff Huxtable on The Cosby Show (1984–1992). He has received numerous awards and honorary degrees throughout his career, many of which were revoked following sexual assault allegations made against him in 2014.

Cosby began his career as a stand-up comic at the hungry i nightclub in San Francisco during the 1960s. Throughout the decade, he released several standup comedy records which consecutively earned him the Grammy Award for Best Comedy Album from 1965 to 1970. He also had a starring role in the television crime show I Spy (1965–1968) opposite Robert Culp. Cosby made history when he won the Primetime Emmy Award for Outstanding Lead Actor in a Drama Series in 1966, making him the first African American to earn an Emmy Award for acting. His acting career continued as he starred in the sitcom The Bill Cosby Show, which ran for two seasons from 1969 to 1971.

In 1972, using the Fat Albert character developed during his stand-up routines, Cosby created, produced, and hosted the animated comedy television series Fat Albert and the Cosby Kids which ran until 1985, centering on a group of young friends growing up in an urban area. Throughout the 1970s Cosby starred in various films including Sidney Poitier's Uptown Saturday Night (1974), and Let's Do It Again (1975), and Neil Simon's California Suite (1978) alongside Richard Pryor. He also starred in the original cast of The Electric Company alongside Rita Moreno and Morgan Freeman from 1971 to 1973. He was also a popular spokesperson in advertising for decades, for various products including the Jell-O ice pop treats Pudding Pop.

Beginning in the 1980s, Cosby produced and starred in the television sitcom The Cosby Show, which was rated as the number one show in America from 1985 through 1989. The sitcom highlighted the experiences and growth of an affluent African-American family. Cosby produced the spin-off sitcom A Different World, which aired from 1987 to 1993. He also starred in The Cosby Mysteries (1994–1995), the sitcom Cosby (1996–2000) and hosted Kids Say the Darndest Things (1998–2000). He then created and produced the animated children's program Little Bill (1999–2004). He was awarded the Presidential Medal of Freedom by George W. Bush in 2002.

Cosby has been the subject of numerous sexual assault allegations which became highly publicized in 2014, after Hannibal Buress brought them back into the public spotlight during a stand-up routine, prompting more women to come forward with accusations. Following the allegations, media organizations pulled reruns of The Cosby Show and other television programs featuring Cosby from syndication. In 2018, he was convicted of aggravated indecent assault against Andrea Constand. He was imprisoned until the conviction was vacated in June 2021 by the Supreme Court of Pennsylvania, for violations of Cosby's 5th Amendment and 14th Amendment due process rights. Cosby's legal issues have continued following his release from prison.