aiko (born Aiko Yanai (????) on November 22, 1975 in Suita, Osaka Prefecture, Japan) is a Japanese pop singer-songwriter. She studied popular music vocals at the Osaka College of Music, graduating in 1996. aiko is known for her cheerful disposition. Her music, which is primarily love songs, reaches a wide audience all over East Asia and beyond. Oricon published the results of a survey with 20,000 subscribers' favourite singers, and aiko headed the list.