In schools and libraries across the country, today is Read Across America Day, part of an effort to encourage kids to read. Why today? It’s the birthday of perhaps the greatest children’s book author of all time, Dr. Seuss.

• “Dr. Seuss” isn’t his real name, of course. The good doctor’s real name is Theodor Geisel—Seuss is his middle name and mother’s maiden name.) He started using it as a student at Dartmouth, when after being caught with contraband gin in his dorm room he had to resign from his position at the campus magazine. He kept working on the publication under his new, assumed name.

• Despite the fact that we’ve all been pronouncing it “Soose” all this time—and that there was a Broadway musical called Seussical (rhyming with “musical”), that isn’t the correct pronunciation. It’s actually pronounced “zoyce.”

• The first Dr. Seuss children’s book: And to Think That I Saw It on Mulberry Street. Published in 1937…it would’ve been published a lot earlier had 27 publishers not rejected it before Random House recognized it had a winner.

• Dr. Seuss’s books are designed for early readers, but in 1960 his editor Bennett Cerf gave him a true challenge for a children’s book: write a book using only different words or less. He did it. The book: Green Eggs and Ham.

• What’s remarkable about his 1950 book If I Ran the Zoo? It coins the word “nerd.”

• Several of Seuss’s books have been adapted into movies, including The Cat in the Hat and How the Grinch Stole Christmas. In 1953, Dr. Seuss wrote his first and only full-length live action movie. And boy is it weird. The 5,000 Fingers of Dr. T. It’s about a little boy who hates taking piano lessons, which drives him to defeat his evil piano teacher’s nefarious plan to force 500 kids to play a giant piano nonstop. Seuss also had a hand in the set design and songs.