Theodor Seuss Geisel (1904 – 1991) was an American writer, cartoonist, animator, book publisher, and artist best known for authoring children’s books under the pen name Dr. Seuss. His work includes several of the most popular children’s books of all time including: If I Ran the Zoo (1950), Horton Hears a Who! (1955), If I Ran the Circus (1956), The Cat in the Hat (1957), How the Grinch Stole Christmas! (1957), and Green Eggs and Ham (1960). He published over 60 books during his career, which have spawned numerous adaptations, including 11 television specials, four feature films, a Broadway musical, and four television series.