Yoko Ono is a Japanese multimedia artist, singer, songwriter, and peace activist. She is best known for her work in avant-garde art, music, and filmmaking, as well as her marriage to John Lennon of the Beatles. The term 'ONO' is an acronym of her name, which stands for 'Ohno Yoko'. She has been an influential figure in the world of art and music since the 1960s, and continues to be a powerful voice for peace and social justice.