In law, failure to exercise the degree of care expected of a person of ordinary prudence in protecting others from a risk of harm. It may render one civilly and sometimes criminally liable for resulting injuries. The doctrine of negligence does not require the elimination of all risk, but rather only foreseeable and unreasonable risk. Thus a higher standard applies to explosives manufacturers than to manufacturers of kitchen matches. The plaintiff must ordinarily prove the defendant's negligence with a preponderance of evidence. See alsocontributory negligence.