DUI stands for Driving Under the Influence, while DWI stands for Driving While Intoxicated or Driving While Impaired. “OWI,” or Operating While Impaired, is also used in some cases, as is “DUID,” or Driving Under the Influence of Drugs. These terms refer to driving while under the effects of alcohol or drugs that impair judgment—a serious crime. DUI and DWI may sometimes be used interchangeably or, in some states, be recognized as different crimes.
The drugs in use do not have to be illegal for a DUI or DWI to be issued; they can be narcotics, over-the-counter medications, or prescription drugs. The focus, instead, is on impaired driving, which is dangerous to both the driver and others on the road.