In short, there is no difference between a DUI and a DWI, they are two ways of saying the same thing.
DWI – This stands for driving while intoxicated or impaired. The term used to refer only to driving under the influence of alcohol but has been updated to include impairment caused by drug usage.
DUI – This stands for driving under the influence, and can refer to the influence of both prescription or illegal drugs or alcohol. This is the term used in Pennsylvania law, so if you live in the Greensburg area or Westmoreland County and have been charged with operating a vehicle while under the influence, it will be a DUI charge.