Step 1 : Introduction to the question "Which book uses exactly 50 different words?"
Green Eggs and Ham is a children's book written by Theodor Seuss Geisel under his pen name Dr. Seuss. Seuss began writing Green Eggs and Ham after his editor Bennett Cerf bet him $50 that he could not write an engaging children's book using a vocabulary of only 50 distinct words. Dr. Seuss accepted the challenge and, with his characteristic creativity and wordplay, began writing Green Eggs and Ham. The book, published in 1960, not only met the challenge but also became one of the best-selling children's books of all time.