a Dr. Seuss book
A Dr. Seuss book is seen as children play during a press preview of an interactive exhibition dedicated to Dr. Seuss at the Children's Museum of Manhattan on July 6, 2004, in New York City. Getty Images

Theodor Seuss Geisel, known to most as Dr. Seuss, was one of the most beloved children’s book authors of all time. Although the artistic writer and illustrator may be best known for his works “The Cat in the Hat,” “Green Eggs and Ham,” “How the Grinch Stole Christmas” and “The Lorax,” the Massachusetts native was responsible for a whole lot more than just the 44 books published under his famous moniker. Those were just some of the reasons why little readers all over the nation will celebrate Seuss and his accomplishments on Read Across America Day on Thursday.

Gear up for a fun day filled with books and check out a few interesting facts about Seuss below:

1. He drew ads before writing children’s books: Seuss didn’t publish his first children’s book under the Dr. Seuss brand until he released “And to Think That I Saw It on Mulberry Street” in 1937. However, he had a flourishing career in advertising well beforehand, drawing ads for companies like Standard Oil and Flit bug spray.

2. He used his art for World War II propaganda: Seuss published political cartoons condemning Hitler and the Nazi regime for left-wing New York newspaper PM in early 1941. Although Seuss was reportedly interested in actually joining the war and wanted to enlist in the Navy, he was instead recruited by director Frank Capra to create a short, “Situation Normal, All Fouled Up,” in which cartoon character Private Snafu taught new recruits how to be a soldier.

3. He wrote two adult books: Despite Seuss’ famous drawings and children’s book, his exploration into adult fiction didn’t go over quite well with audiences. His first book, which featured drawings of naked ladies all throughout and was titled “The Seven Lady Godivas: The True Facts Concerning History’s Barest Family,” tanked in sales. He later released another adult picture book, “You’re Only Old Once,” which did better but still never received the same kind of praise as his colorful children’s books.

4. He created the term “nerd”: Before Dr. Seuss, there was no documented reference for the word. The writer first included the term while describing a yellow-and-white-haired sourpuss in the book “If I Ran the Zoo.”

5. He initially aspired to be a professor: Although Seuss became an educator in his own right, in the earliest beginnings of his career he set out to be a professor. After graduating from Dartmouth College, Seuss left the U.S. for England, where he studied at Oxford University. However, he dropped out in 1927 and returned to the states to pursue cartooning full-time.

CORRECTION: An original version of this article incorrectly stated the date for Read Across America Day. It is on Thursday.