There are at least two artists who use this name
1. A musician from South Korea
2. An acoustic musician from England
3. A French electronic artist

1) A romanisation of 싸이 (Hangul, often stylized as PSY), a pseudonym of Park Jae-sang (Hangul: 박재상; born December 31, 1977) is a South Korean singer-songwriter, model, rapper, dance musician and record producer. He is popular for his humorous videos and stage performances, and has appeared on numerous television programs