A pedometer is a device that counts the number of steps a person takes. It typically uses a motion sensor to detect movement and can be worn on the body, such as on a belt or in a pocket. Pedometers are often used to track physical activity and encourage a more active lifestyle. Many modern pedometers also include additional features, such as tracking distance traveled, calories burned, and even heart rate. Some devices can connect to smartphones or fitness apps, allowing users to monitor their progress over time and set fitness goals. Popular brands include Fitbit and Garmin.