Not all cats purr. Cats that purr cannot roar. Cats that roar cannot purr. Humans have long researched and studied cats to determine specifically what the mechanism is that enables some cats to purr while others cannot. Details of that discussion were in July’s Mews ‘N News Article “How Do Cats Purr?”
Cats that do purr are: the Domestic Cat, Bobcat, Ocelot, Lynx, Puma, Cougar, Serval and the Cheetah. They are in the Felinae Subfamily. ALL cats are of the Felidae family.