A products liability negligence claim usually falls into one of three possible types: those claiming a design defect, a manufacturing defect, or a failure to warn. Over time, several other negligence concepts have arisen to deal with certain specific situations, including negligence per se (using a manufacturer's violation of a law or regulation in place of proof of a duty and a breach) and res ipsa loquitur (an inference of negligence under certain conditions). The difficulties of an injured customer to prove what a manufacturer did or did not do during the design or manufacture of product has led to the development of newer product liability claims such as strict liability.