Driving Under the Influence, often abbreviated as DUI, refers to operating a vehicle while impaired by alcohol or drugs. This impairment can affect a person's ability to make sound judgments, react quickly, and maintain control of the vehicle, increasing the risk of accidents. Laws regarding DUI vary by location, but they typically involve legal limits for blood alcohol concentration (BAC). Penalties for a DUI conviction may include fines, license suspension, and even jail time, depending on the severity of the offense and whether it resulted in injury or damage.