There is more than one artist with this name:
1) "M" is the name of a pop band from the '70s and '80s, fronted by singer/songwriter Robin Scott.
2) "M" is Mathieu Chedid, a french singer born in 1971. For more, see also "-M-" for an alternate labelling convention.
3) "M" (이민우/Lee Minwoo/Minwoo) is a South Korean pop/r 'n b singer. He is also a part of the longest running boyband in South Korea, "Shinhwa".
4) "M" was a German Dancefloor-Project consisting of producers Joachim Muno and Udo Niebergall.