Carfax has announced that it has surpassed the 3 billion mark in its online database of vehicle history records. Each data record is associated with a specific vehicle, identified by a 17-character vehicle identification number. Buyers and sellers of used cars use these pieces of information to learn more about a car's past that may include routine maintenance and odometer readings or uncover department of motor vehicle-reported incidents including prior salvage records, flood damage, or other branded titles.