An axle counter is a device used in railway systems to detect the presence of trains on tracks. It counts the number of axles that pass a specific point, helping to determine if a section of track is occupied or clear. This information is crucial for ensuring safe train operations and preventing collisions. Axle counters work by using sensors placed along the track. When a train passes, the sensors detect the axles and send data to a central control system. This system can then manage train movements and signal changes, contributing to the overall efficiency of the railway network.