International Nonproprietary Names (INNs) provide a unique name for each pharmaceutical substance to aid clear identification and safe use worldwide. The WHO manages the INN system, selecting names through a process involving proposed names, an objection period, and final recommended INNs. INNs aim to identify substances uniquely while avoiding names that could cause confusion or be proprietary. Principles for selection include being distinctive, concise, and avoiding confusion with other names. Stem elements are often used to group related substances.