Research overview: the many contexts and functions of purring

Purring is most associated with contentment, but cats also purr when injured, frightened, giving birth, or near death, prompting research into its varied functions. This overview surveys evidence that purring serves as a close-range affiliative signal between mother and kittens and between cats and humans, and discusses hypotheses that the low-frequency vibrations may have self-soothing or even tissue-supporting roles, while noting these remain speculative. It also covers the solicitation purr that exploits human caregiving. The topic explains why a single signal appears across such contradictory situations and why purring is best understood as a multifunctional close-contact vocalisation rather than a simple happiness indicator.