Vehicle speed refers to how fast a vehicle, such as a car or truck, is moving at a given moment. It is typically measured in units like miles per hour (mph) or kilometers per hour (km/h). Speed can be influenced by various factors, including road conditions, traffic, and the vehicle's engine performance. Monitoring vehicle speed is important for safety and efficiency. Adhering to speed limits, which are set by local authorities, helps reduce the risk of accidents. Additionally, maintaining an appropriate speed can improve fuel efficiency, benefiting both the environment and the driver's wallet.