The Metro-Goldwyn-Mayer cartoon studio was the in-house division of Metro-Goldwyn-Mayer (MGM) motion picture studio in Hollywood, California during the Golden Age of American animation, responsible for producing animated short subjects to accompany MGM feature films in Loew's Theaters. Active from 1937 until 1957, the MGM cartoon studio produced some of the most popular cartoon series and characters in the world, including Barney Bear, Droopy, and their best-known work, Tom and Jerry.Prior to the existence of their in-house cartoon studio, MGM released the work of independent animation producers Ub Iwerks and Hugh Harman and Rudolph Ising.