The Cat in the Hat of all time. As of 2007, more than 10 million copies of "The Cat in the Hat" have been printed, and it has been translated into more than 12 different languages, including Latin, under the title "Cattus Petasatus". In 2007, on the occasion of the book's fiftieth anniversary, Random House released "The Annotated Cat: Under the Hats of Seuss and His Cats", which includes both "The Cat in the Hat" and its sequel, with annotations and an introduction by Philip Nel. The book was published to immediate critical acclaim. Some reviewers praised the book as an exciting way to learn
The Cat in the Hat for the series, including "The Cat in the Hat Comes Back" (1958), "Green Eggs and Ham" (1960), "Hop on Pop" (1963), and "Fox in Socks" (1965). He initially used word lists of limited vocabularies to create these books, as he had with "The Cat in the Hat", but moved away from the lists as he came to believe "that a child could learn any amount of words if fed them slowly and if the books were amply illustrated". Other authors also contributed notable books to the series, including "A Fly Went By" (1958), "Sam and the Firefly" (1958), "Go, Dog.