The difference between a DUI and a DWI depends mainly on the respective definitions given by the state in which the arrest is made. In most states, the only difference is in the acronym. DUI stands for "Driving under the Influence," while DWI stands for "Driving while Intoxicated. However, in some states, there is a legal distinction between the two. In these states, a DUI generally carries a lighter punishment. A DUI indicates that the driver was operating his or her vehicle at a lesser degree of intoxication.