Cats have tails as a way of communicating their feelings and desires, and also the supracaudal glands found on the surface of the tails are responsible for releasing a unique and distinct scent that is used for marking territory. When annoyed, cats normally make a quick tail swishing motion.
Although people in the past believed that docking tails helped ward off medical diseases and illnesses, this has found to be untrue. Some cats, like Manx cats, have short tails, and are still able to live long and fulfilling lives.
Although tail docking is a possibility for pet owners who do not wish for their cats to have tails, most veterinarians now question the ethics surrounding this surgical procedure.