A milometer is an instrument used to measure distances, usually in miles or kilometers. There are several synonyms for milometer, including odometer, which measures the distance a vehicle travels; pedometer, which measures steps taken while walking; and cyclometer, which measures the distance a bicycle travels. Other synonyms include mileometer, kilometre meter, and distance meter. Some modern milometers are digital, while others are mechanical, and many can display additional information, such as the speed of the vehicle. Although these instruments go by different names, they all serve the same purpose of measuring distance in some way or another.