Masters of the Universe (abbreviate to MOTU) is a media franchise created by Mattel. Among others, it features the characters of He-Man and Skeletor. Since its initial launch in 1981, the franchise has spawned four animated television series, several comic series, a film and numerous action figures. Designer Roger Sweet claims to be the chief creator of He-Man and MOTU, although this is not officially acknowledged by Mattel. The earliest storybooks and much of the original backstory were written by Donald F. Glut.