Taming mt 4 year old cat?

I got her when she was 6 weeks old. I think she was born with a bad temper She will scratch and bite you for no reason
Answers:
Cat owners sometimes have difficulty understanding why their cats seem friendly and content one minute and may suddenly bite and scratch them the next. Aggressive behaviors are part of the normal behavioral patterns of almost any animal species. Cat bites are seldom reported, but probably occur more frequently than dog bites. Aggressive cats can be dangerous, so attempting to resolve a cat aggression problem often requires assistance from an animal behavior specialist who is knowledgeable about cat behavior.

Types Of Aggression
Play Aggression
Play-motivated aggressive behaviors are commonly observed in young, active cats less than two years of age, that live in one-cat households. Play incorporates a variety of behaviors, such as exploratory, investigative and predatory, and provides young cats with opportunities to practice skills they would normally need for survival. For example, kittens like to explore new areas and investigate anything that moves, and may bat at, pounce on, and bite objects that resemble prey.

Playful aggression often occurs when an unsuspecting owner comes down the stairs, steps out of the bathtub, rounds a corner, or even moves under the bedcovers while sleeping. These playful attacks may result in scratches and inhibited bites which don't break the skin. People sometimes inadvertently initiate aggressive behavior by encouraging their cat to chase or bite at their hands and feet during play. The body postures seen during play aggression resemble the postures a cat would normally show when searching for or catching prey. A cat may freeze in a low crouch before pouncing, twitch her tail, flick her ears back and forth, and/or wrap her front feet around a person's hands or feet while biting. These are all normal cat behaviors, whether they're seen during play or are part of an actual predatory sequence. Most play aggression can be successfully redirected to appropriate targets, however, it may still result in injury (see our handout: "Managing Your Kitten's Rough Play").

"Don't Pet Me Anymore" Aggression
Some cats will suddenly bite while they're being petted. This behavior isn't well understood, even by experienced animal behaviorists. For whatever reason, petting which the cat was previously enjoying, apparently becomes unpleasant. Biting is the cat's signal that she has had enough petting. Cats vary in how much they'll tolerate being petted or held. Although people often describe their cats as biting "out of the blue" or without warning, cats do generally give several signals before biting.

You should become more aware of your cat's body postures, and cease petting or stop any other kind of interaction before a bite occurs. Signals to be aware of include:

Restlessness
Your cat's tail beginning to twitch
Your cat's ears turning back or flicking back and forth
Your cat turning or moving her head toward your hand
When you observe any of these signals, it's time to stop petting your cat immediately and allow her to sit quietly on your lap or go her own way, whichever she prefers. Any kind of physical punishment almost always makes the problem worse, because your cat is more likely to bite either because she is fearful and/or because petting becomes even more unpleasant if it's associated with punishment.

If you want to try to prolong the amount of time your cat will tolerate petting, use some food rewards. When your cat first begins to show any of the behaviors described above (or even before she does so) offer her a special tidbit of food like a tiny piece of tuna or boiled chicken. At the same time, decrease the intensity of your petting. Continue to lightly pet your cat for a short time period while offering her tidbits. In this way, she'll come to associate petting with pleasant things and it may help her to enjoy petting for longer time periods. Each time you work with your cat, try to pet her a little longer each time using the food as a reward. Be sure to stop the petting before she shows any aggression. If a display of aggression results in the petting being stopped, then this unacceptable behavior has worked.

What Not To Do
If your cats are fighting, don't allow the fights to continue. Because cats are so territorial, and because they don't establish firm dominance hierarchies, they won't be able to "work things out" as dogs sometimes do. The more often cats fight, the worse the problem is likely to become. To stop a fight in progress, make a loud noise, such as blowing a whistle, squirting the cats with water, or throwing something soft at them. Don't try to pull them apart.
Prevent future fights. This may mean keeping the cats totally separated from each other while you're working on the problem, or at least preventing contact between them in situations likely to trigger a fight.
Don't try to punish the cats involved. Punishment is likely to elicit further aggression and fearful responses, which will only make the problem worse. If you attempt punishment, you may become a target for redirected and defensive aggression.
Because their social organization is somewhat flexible, some cats are relatively tolerant of sharing their house and territory with multiple cats. It's not uncommon for a cat to tolerate some cats, but not get along with others in the house. However, the more cats sharing the same territory, the more likely it is that some of your cats will begin fighting with each other.

When you introduce cats to each other, one of them may send "play" signals which can be misinterpreted by the other cat. If those signals are interpreted as aggression by one of the cats, then you should handle the situation as "aggressive."

The factors that determine how well cats will get along together are not fully understood. Cats that are well-socialized (they had pleasant experiences with other cats during kittenhood) will likely be more sociable than those that haven't been around many other cats. On the other hand, "street cats" that are in the habit of fighting with other cats in order to defend their territory and food resources, may not do well in a multi-cat household. Genetic factors also influence a cat's temperament, so friendly parents are probably more likely to produce friendly offspring.

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If your cat has not always done this, then check for a medical condition that is aggravating it.
If your cat has always had 'issues', then I suggest some form of discipline. The cat needs to know that it is not acceptable.
You could also have it declawed if necessary.
Wish you luck!
Cheers