Cats use an elaborate system for communicating with each other and other species. Body language, scent, touch, and sound are all important factors in communication and will also help you to determine their mood.
Follow the nose!
A cat smells to learn about their environment and the other cats that live in it. Scent marking is possible by glands found in a cats chin, forehead and on top of the tail, as well as urine and faeces. So when your cat affectionately rubs up against your legs or your lounge room sofa, he/she is actually rubbing scent from their cheek glands on to you or the furniture.
Facial expressions, body posture and tail movement all indicate a cat's mood. To determine what your cat is thinking you should observe their body language as a whole not just isolate one aspect of it.
A relaxed contented cat points their ears forward, half closes their eyes, curls the tail and purrs. A cat that is afraid will have their ears back folded flat on the head, and their pupils will be dilated. An agitated cat has completely dilated pupils, flattened ears, forward sweeping whiskas, and may even show his/her teeth. A defensive cat will make themselves as big as possible, including brushing their tail out and extending their legs and backbone. And, if you see a quickly twitching tail, this indicates excitement or imminent aggression.
Purrr.. the sound of a cat
The pitch, intensity, frequency, rapidity and volume of a cat's meow reflect their different emotional states and physical needs. Cat's use sound for different reasons, to communicate between offspring, to communicate with adults in their territory or with other species such as humans. Purring indicates a calm relaxed state although some cats also purr when they are in pain. Vowel patterns indicate a need for food or other desires. Loud strained intense sounds including hissing, screaming and growling are often associated with mating or aggressive behaviours.
Cat's also leave visual messages for other cats. Confident cats are more likely to scratch and do so in front more subordinate cats.
A cat as individual as you!
Every cat is different and over time every cat owner learns their cat's unique way of communicating. Learning and understanding how your cat communicates will assist you in forming a special bond with your pet. Being able to observe any changes in the way your cat communicates and behaves can also provide useful information about your pet's health.