Purring – Purring is often a sign of contentment. Some cats purr when they are in extreme pain, or in labour, simply to try to calm themselves down. Purring therefore can be a sign of pleasure or pain; usually it is the former. Scientists have not yet been able to discover how purring works, but it is suspected that it is caused by minute vibrations in the voice box.
Scientists at the University of Sussex showed in 2009 that purring, or some purring, seems to be a way for domesticated cats to signal their owners for food. Purring in the “about to be fed” context has a high-frequency component not ordinarily present. This has been called “soliciting purring”.
Greeting – A particular sort of vocalization, such as a low meow or chirp or a bark, possibly with simultaneous purring.
Distress – Mewing is a plea for help or attention often made by kittens. There are two basic types of this call, one more loud and frantic, the other more high-pitched. In older cats, it is more of a panicky repeated meow.
Attention – Often simple meows and mews in both older cats and young kittens. A commanding meow is a command for attention, food, or to be let out.
Protest – Whining meows.
Frustration – A strong sigh or exhaled snort.
Happy – A meow that starts low then goes up and comes back down.
Watching – Cats will often “chatter” or “chirrup” on seeing something of interest. This is sometimes attributed to mimicking birdsong to attract prey or draw others’ attention to it, but often birds are not present.