Scared and angry cats hold their hair straight up to appear bigger in the early stages of fear and aggression. Some cats with the big fluffy tails just puff them out.
Whiskers have a broader expressive emotion. If a cat is curious or angry, he holds his whiskers forward (cats also do this in the dark to help them "feel" their way around). They pull their whiskers backward when they are frightened.
Most cats have 24 whiskers, divided on both sides of the nose and arranged in four horizontal rows. The top rows and bottom rows can move independently of each other and each whisker. Even though whiskers are important to cats- your pet may become disoriented if they're removed, which is why you should never cut them.
Posture:
The way a cat holds her body must be observed along with signs from the tail, ears, eyes, voice, and fur (including whiskers) to correctly find out what your cats emotional state is. A cat who enjoys being petted from head to toe often arches her back to maximize contact with your hand.
in another situation an arched back may mean you shouldn't even go near her cause you might get hurt.
Here are three positions of a cat and what they mean:
Inquisitive - The friendly and curious cat is relaxed, moving forward comfortably with tail up. Ears are up, too, and slightly pointed to the sides.
Defensive - A cat who's just angry or scared arches her back and puffs out her fur in the classic "Halloween cat" pose.
Aggressive - A cat who's going to attack crouches low, his back a little higher than his front, ready to put his powerful hind legs to use in a leap forward. the fur over his shoulders is up, as is the fur on his tail. This cat
means business; back away and let him be!
A cat in an aggressive or defensive posture, is best to be left alone. Even if he's your cat, give him time to chill out before you even attempt to approach him. He'll be fine after a little while. Even cat's have temper tantrums.