Why Do Cats Knead?

Kneading is a common behavior seen in domestic cats, in which the feline pushes in and out with its front paws, alternating between left and right.

Cats often perform this motion — sometimes called "kneading dough" or "making biscuits" — on soft surfaces, including pillows, blankets, other animals and even people.

It's unclear why cats knead, but a number of hypotheses exist. [20 Weird Dog and Cat Behaviors Explained by Science]