You may probably have asked yourself why cats purr and, in fact, this phenomenon has been the object of much research by different authors. Some of them will describe it like a soft and continuous buzzing, exclusive in felines, which is accompanied by a vibration in the animal´s body.
There are different conclusions about what causes this peculiar noise in felines, however, there is not a definitive theory since cats purr in different situations. The most regular situation for purring is when the feline feels at ease, calm and content. That´s why is normal to do so when they are being petted.
Nevertheless, that gentle rumble is not synonymous of pleasure. Cats can purr in basically almost every situation, from those moments when they are comfortable and happy until even minutes before they pass the way. They can also purr in front of other cats, and in this case, it would be a way to avoid a fight and to convey the message of being calm.
The fact that these little felines purr in such different situations, may indicate that this phenomenon will be present when they experience intense emotions.