Björk Guðmundsdóttir (, born 21 November 1965), known mononymously as Björk , is an Icelandic singer-songwriter, multi-instrumentalist, and occasional actress. She initially became known as the lead singer of the alternative rock band The Sugarcubes, whose 1987 single "Birthday" was a hit on US and UK indie stations and a favorite among music critics. Björk embarked on a solo career in 1993, coming to prominence as a solo artist with her single "Human Behaviour" and her album Debut. She has since had 30 singles reach the Top 40 on pop charts around the world, with 22 Top 40 hits in the UK, including the Top 10 hits "It's Oh So Quiet", "Army of Me", and "Hyperballad". Additionally, "Big Time Sensuality", "Hyperballad" and "I Miss You" were number one Dance Hits in the US. Over her three-decade career, she has developed an experimental and eclectic musical style that draws on a wide range of influences and genres spanning electronic music, dance, pop, and the avant-garde. Critics have consistently praised Björk's work, praising her innovative approach to singing and composition, her musical experimentation, her music videos, and her distinctive voice; she has been described as "the most important and forward-looking musician of her generation" and "the best non-pop female vocalist of the last 30 years."

Bjørk is a Faroese, Danish & Norwegian given name meaning “birch”. Bjørk is today also used for female, but the female variant of the name is Bjørg.