She’s showing affection.
If you think your cat is expressing her love for you when she licks you, you’re likely right. “Cats that have a relationship with one another—be it mother and child, siblings, or just friends—will groom each other as a sign of affection,” she says. “The same [is true] when your cat licks you.”
She’s teaching you how to groom.
Cats groom one another. House cats’ wild relatives groom each other so that they don’t attract predators, while house cats have a maternal instinct and want to teach their kittens how to keep themselves clean. “To a cat, it doesn’t matter that you are human,” Ochoa says, and “once they have come to care for you, they will treat you the same way as any member of its group.” That includes grooming you and—in their minds, at least—teaching you how to groom yourself.
She’s marking her territory.
We all know—some from unfortunate experience—that male cats will spray urine to mark their territory. “But by licking you, they are also marking you as their territory,” says Ochoa. Why? “It’s a way of letting other cats know they care about you, and you belong to them,” she says.
She’s helping you keep calm.
Cats can be very empathetic. And “if your cat senses you are stressed or sick, it may lick to help calm you down or make you feel better, just like it would another cat in the wild,” says Ochoa. It’s a behavior your cat likely learned from her mother who did it to her. “By licking or rubbing their head against you, they really are showing you how much they care about you,” Ochoa says.