Taeil (Hangul: 태일), born Moon Taeil (Hangul: 문태일) in Seoul, South Korea on June 14, 1994 is best known as the oldest member and main vocalist of South Korean boygroups NCT U and NCT 127. Taeil was introduced as part of SM Rookies in October 2015. On January 27, 2016, he released the song "Because of You" for the soundtrack of the series The Merchant: Gaekju 2015. On December 29, 2016, he released the song "Sound of Your Heart" for SM Station as part of SM Town.