Cats use scent to communicate, as well as body language. The scents they use are called “pheromones,” which are secreted by glands on their foreheads, lips, front paws, flanks, and rears. Because each cat produces its own “formula” of pheromone, cats can use pheromones to recognize each other. When a cat applies her own pheromones to an object or to another animal or person, she is using the scent to mark that object, animal or person as her own. When cats share their pheromones in a group, it might be a way of becoming at ease with each other or creating a pecking order.