"I'll be honest. I had to Google that," he told reporters. "I guess it's just a generational thing. I didn't get the reference. It's kind of funny, I guess."
But he wasn’t the only one who didn’t initially understand. Want to learn more about the classic caricature. Here are some quick facts.
Who is Alfred E. Neuman?
He is the fictitious character of the humor publication, Mad magazine. The big-eared, gap-toothed boy made his debut on the magazine in 1956, according to Mad's blog. He's appeared on more than 500 issues.
Who’s the illustrator of the cartoon?
Neuman's face was drawn by Norman Mingo. Although Mad's staff had several artists, including Atlanta-born cartoonist Jack Davis, none could "render accurately the Mingo prototype," Mad's blog stated.
» RELATED: Illustrator Jack Davis' NOT-SO-MAD WORLD
Where did the inspiration come from?
Mad editor Harvey Kurtzman saw the image of the boy on a postcard pinned to an office bulletin, according to Mad's blog. When he spotted it, he said, "It was a kid that didn't have a care in the world, except mischief."
Although Kurtzman first noticed the boy in the 1950s, his origin could date back to 1894. Some said he was used to sell medication, while others believe they saw him in textbooks, according to Mad’s site.
Where else has Neuman appeared?
His face has been merged with several U.S. presidents, including George W. Bush, by editorial cartoonists. He’s also been seen in comics like “Beetle Bailey” and “The Amazing Spider-Man.” He’s even appeared in episodes of the comedy sketch show “MadTV” and the animated series “Mad.”
What did Mad think of Trump comparing Buttigieg to Neuman?
Neuman became a trending topic on Twitter following Trump’s remarks. Mad seemed to poke fun at the situation by changing its Twitter bio to “Historic comedy institution with Mayor Pete on the cover.”
It even tweeted covers of the magazine to Buttigieg and post another that read, “Who’s Pete Buttigieg? Must be a generational thing.”
» RELATED: Buttigieg acknowledges work needed to appeal to black voters