An American children's book author and illustrator, he is best known for his Little Critter and Little Monster series for beginning readers. His most famous individual titles include There's a Nightmare in My Closet and If I Had a Gorilla.
During his studies at the Honolulu Museum of Art, he decided to become an illustrator. In 1964, he began training at The Art Students League of New York.
He published more than 300 children's books in all and also illustrated titles by Jan Wahl, Jay Williams, and other writers.
He was born in Little Rock, Arkansas. He had three children with his second wife, Jo Mayer.
Howard Pyle, born almost 100 years before Mayer, was another prominent children's book author and illustrator.