Flavacol is a popcorn seasoning salt widely used in movie theaters to create that signature buttery, salty flavor. It’s a fine, orange-yellow powder made with salt, artificial butter flavor (diacetyl), and coloring agents, which is what gives movie theater popcorn its vibrant color and rich, savory taste.

Movie theater popcorn may seem impossible to recreate at home, but it turns out there's one secret ingredient that makes the classic cinema snack special.

If you love popcorn and a movie, head to your local theater to celebrate National Popcorn Day on Sunday, Jan. 19. To help you enjoy popcorn in all its savory, salty, and sweet forms, movie theaters across the U.

There's no doubt that popcorn is a go-to movie theater snack. But it wasn't always this way. Here's how popcorn became so popular.