Different types of drugs affect people differently and can be categorized based on shared symptomatologies or effects. The DRE categorization process classifies drugs into seven categories: central nervous system (CNS) depressants, CNS stimulants, hallucinogens, dissociative anesthetics, narcotic analgesics, inhalants, and cannabis. Each category of drugs can impact a person's central nervous system and impair their normal faculties, including the ability to operate a motor vehicle safely.