Specific muscles rapidly open and close the cat's voice box creating purr vibrations.
Laryngeal Mechanism
Mother cats purr to soothe nursing kittens who cannot yet regulate their temperature.
Comforting Reflex
Purring helps cats relieve tension, fear or pain by releasing calming endorphins.
Self-Comfort
Ill cats may purr to aid healing through calming, restorative vibrational frequencies.
Sickness Response
Cats purr to signal safety/trust and draw attention from humans or other cats.
Communication
Of course, purring also strongly conveys feline happiness and affection!
Happiness Hums
Every cat's distinctive anatomy gives them a unique purr cadence and tone.
Unique to Each