Everyone knows In-N-Out Burger: Californians have eaten more orders of “Animal Style” fries than they can count, and non-Californians have ex-pat friends who won’t shut up about the burger chain whose cult following makes Shake Shack’s look tame. But just how well do you really know In-N-Out?

The notoriously private chain, family-owned for more than 60 years, isn’t much for publicity, but there’s still plenty to unearth about the Golden State’s most beloved export. We’ve collected ten lesser-known trivia about In-N-Out, from its current president’s lifelong hobby to its most notable celebrity fans. Here are ten things you didn’t know about In-N-Out, so you can devour your next Double Double as a more informed customer.

Written by Alison Herman (@aherman2006)