The Purr: Cats (big and small) are the only animals that purr. Why?
Purring isn't voice-generated; it comes from two membrane folds, called false vocal cords, that's situated in the larynx behind the actual vocal cords. Cats purr at 26 cycles per second, the same frequency as an idling diesel engine. They can purr both on inhaled and exhaled breaths, with their mouths completely closed. Scientists think purring is produced by blood in a large vein in the chest cavity that vibrates and is then magnified by air in the windpipe.
For purring kittens (who are deaf and blind), the vibration of their mother's purring can be felt, acting as a homing device, a signal for them to nurse. Kittens themselves begin purring at one week old, and tells the mother that they're getting all their milk and are content. And since purring is non-vocal, it doesn't interfere with the kitten's sucking.
Cats don't purr just for pleasure; a deep one can also indicate pain or distress. Purring can occur from fear, when females are in labor, or just anticipating something that makes them happy.
The Meow: There are many variations: a short, soft-spoken "mew" is your cat's way of saying "Hi, how are you?" A loud and drawn-out "meo-o-o-o-ow" is a demand for food or attention. A soft "R" noise that ends in a trill means kitty's asking you to come over.
I've also heard a very short, happy-sounding "meo" (or something to that effect!) as I'm preparing food or even in the process of getting it ready. Or as I'm eating!
Cats also talk to you in other ways:
Hearing: They can hear sounds up to 100,000 cycles per second (This happens to be the same sound pitch made by a mouse's squeal. A human's hearing is only one-fifth that of a cat's, and a dog's is only one-third.) This is one of the reasons many people mistakenly believed, as many still do, that cats have supernatural powers. They begin to lose some of this extraordinary hearing by age five, but when they're younger, it's extremely precise. And I believe they also hear what they want to hear!
The Ears: There are five basic ear signals. If they point forward and slightly outward, then every thing's cool. They're relaxed and just listening to everything going on around them. If the ears are erect and facing forward, they're alert and may investigate some noise. If the ears are twitching nervously back and forth, they're agitated or anxious. When the ears are flattened tightly against the head, this means annoyance or feeling defensive. Ears that are sort of at half-mast means kitty's feeling aggressive (but not frightened).
The Tail: A tail waving quietly from side to side is a sign of contentment or concentrating intently on something. A slow twitch of the tail tip means "I'm feeling good." A vigorous lashing back and forth is a clear sign of anger, annoyance, or being upset. If growling accompanies this, back off!
If tail-wagging is somewhere between heavy-duty and half-hearted, this can mean that your cat feels very indecisive at the moment. As soon as kitty's mind is made up, the wagging will stop.
When a fluffy-looking tail is bent forward over the head, it means your cat's feeling like "top dog." Several quick flicks upward is a greeting. A high, quivering tail means "I think you're the best thing in the whole world!"
The Eyes: When your cat looks steadily at you, giving you several long, slow blinks, you're getting the equivalent of a kiss! How to say "I love you" back? Blink back at kitty the same way!
If the pupils are narrow and dilated, this means "I'm annoyed." If you get on kitty's level and speak to your cat while sitting on the floor, it will immediately make your cat feel more comfortable.
The Whiskers: They're one of your cat's most delicate sense organs. By bending the whiskers, kitty can magnify the smallest air disturbance. Whiskers grow at the side of the mouth in four rows and above the eyes. There are about 25-30 of them, each attached to a nerve in the skin. They aid your cat's movement in the dark.
And they're also a means of communication. Are they sticking straight out to the side? Kitty's content. Are they lying flat against her cheeks? Your cat's afraid and feeling defensive. You can reassure kitty by approaching from the side, not head-on. You'll instantly appear more friendly (A head-on approach and a direct stare, any type of staring, is seen as threatening).