If you were to walk up to a friend in public and show each other your bare butts, you’d probably get a lot of very strange looks from the rest of the people in the Starbucks line. If you were a cat, however, people would probably just roll their eyes and accept that cats just can’t get enough of showing humans their behinds. As it turns out, when your cat flashes its butthole to you it’s really just their own version of a handshake.

Longtime cat owners are plenty used to this by now, but cats really, really love their own butts, and they’re not shy about showing them off. Petting any average house cat has about a 50% chance to result in the cat raising its tail high and showing off its dirtiest of orifices. As cat researcher Mikel Delgado explained to Inverse, that’s really just the way cats are programmed.

“For cats, it’s normal for them to sniff each other’s butts as a way to say hello or confirm another cat’s identity,” Delgado told the site. “It’s hard for us to relate to, but for them, smell is much more important to cats and how they recognize each other than vision is. So cats may be ‘inviting’ us to check them out, or just giving us a friendly hello.”

Cats, not unlike dogs, communicate a lot through scent. When you pet your cat, you’re sharing your scent with them and allowing them to place their own scent on you. Because cats are territorial by nature, the “butt scent” is one way they communicate who they are and allow other animals to know what they’ve laid claim to. When your cat raises its tail it’s a sign that they’re greeting you in the most intimate way they can, and it’s a sign that your cat sees you as someone to be trusted.

By contrast, a feline that keeps its tail locked in a downward angle may not be comfortable with the situation they’re in. “Kitties that keep the tail down and don’t want to be sniffed might be compared to a shy person hiding their face,” cat behaviorist Amy Shojai says.

So the next time your furry friend flashes their nether regions, don’t take it as an insult, but rather a compliment.