Adorable cat lying on top of an open book on a knitted blanket

This cat is purring up a storm. (Image credit: Liudmila Chernetska)

Purring, a gentle vibration that domestic cats make as they breathe in and out, is unique to cats and cat-like animals. Cougars, cheetahs, and some other big cats also purr; so do civets, genets, and mongooses. But why do cats purr?

“It’s one of those behaviors that we mostly understand, but not quite,” he said. Mikel Delgado, (opens in a new tab) a certified feline behavior consultant at Feline Minds, told Live Science. “The purring is probably reflexive, like breathing.”