Definition:
In short, negligence is the basis of almost all personal injury lawsuits, (But see Strict Liability and Intentional Tort) including medical malpractice, automobile accidents, and defective products. In each of those cases, a plaintiff needs to prove (among other things) that the defendant either did something a "reasonable person" wouldn't do, or didn't do something a reasonable person would do in similar circumstances.
The definition and application of negligence and the reasonable person standard varies from state to state, but one thing that doesn't vary is the fact that a plaintiff has to prove a defendant was negligent before he or she can win any money. The negligence standard takes into consideration that sometimes bad things just happen.
In a product liabilty case, for example, it could be undisputed that the plaintiff used a product and was severely injured by the product. But if the jury doesn't believe the defendant was negligent in designing, building, or selling the product, the defendant wouldn't owe the plaintiff any money - no matter how badly the plaintiff was hurt by the defendant's product.
Pros:
The negligence standard means that in most cases, a defendant has to have done something "wrong" in order to owe a plaintiff any money.
Cons:
Sometimes, plaintiffs who are injured through no fault of their own aren't entitled to even get their medical bills paid, because the defendant didn't do anything wrong, either.
The Controversy:
The controversy over the negligence standard isn't fought in the political arena, but in the courthouses of America every day. Most injury cases aren't decided upon whether or how badly the plaintiff was hurt, but whether the plaintiff's injuries were caused by the defendant's negligence. Only if the defendant's negligence was the cause of the plaintiff's injuries do juries determine how much money, if any, to award the plaintiff.
For More Information:
Alternative Rules of Determining Tort Liability: Negligence
Prudence, Benevolence, and Negligence: Virtue Ethics and Tort Law