George Pal (b. Feb. 1, 1908 - d. May 2, 1980) was a filmmaker and visual effects pioneer who specialized in animated short films early in his career, and who later branched out into feature films. His film career spanned forty years, producing fourteen feature films, and miscellaneous short films.
It is difficult to say precisely what Pal is most recognized for; his animated short films called Puppetoons, or his feature films. Suffice to say, his body of work has stood the test of time, and has made a lasting impression on western culture.
There are a couple of links to Pal's work in the menu section. One labeled Puppetoons will take you to a page that talks about the animated short films he produced, and another called Movies, which lists the motion-pictures that he made.