Cats communicate with each other using vocalizations, body language, and scent signals. Vocalizations include meowing, purring, chirping, and hissing. Body language includes postures, facial expressions, and tail movements. Scent signals include urine marking, rubbing against objects, and releasing pheromones. Cats use these signals to express a variety of emotions and messages, such as aggression, submission, and friendship. Understanding these signals can help owners better understand their cat's behavior and needs.