Cats communicate with each other through a variety of vocalizations, body language, and scent marking. Common vocalizations include meowing, purring, hissing, and growling. Meowing is typically used to communicate with humans, while purring is a sign of contentment. Hissing and growling can be used to express aggression or fear. Cats also communicate through body language, such as arching their backs, raising their fur, and flicking their tails. Finally, cats use scent marking to mark their territory and identify other cats.