Devilman (デビルマン, Debiruman?) is a Japanese manga series written and illustrated by Go Nagai which originally started as an anime adaptation of the concept of Nagai's previous manga series, Mao Dante. A 39-episode anime TV series was developed by Toei in 1972 and Nagai began Devilman as a manga in Kodansha's Shōnen Magazine, barely a month before the TV series started. The series has since spawned numerous other anime, manga and films.

Source: Wikipedia