Blood Alcohol Content (BAC) is a measurement that indicates the amount of alcohol present in a person's bloodstream. It is expressed as a percentage, representing the grams of alcohol per deciliter of blood. For example, a BAC of 0.08% means there are 0.08 grams of alcohol for every 100 milliliters of blood. This measurement is commonly used to assess a person's level of intoxication. BAC levels can affect a person's ability to perform tasks, such as driving. Different countries have varying legal limits for BAC while operating a vehicle, often set at 0.08% for adults. Higher BAC levels can lead to impaired judgment, coordination, and reaction times, increasing the risk of accidents.