The "dipper" in a car refers to the functionality of adjusting the beam of headlights between high beam and low beam. This feature is crucial for ensuring safe driving, especially during nighttime or low-visibility conditions. The high beam provides brighter and longer light coverage, ideal for highways and roads without oncoming traffic. Conversely, the low beam minimizes glare for oncoming drivers, enhancing road safety. Drivers are encouraged to use the dipper responsibly to maintain visibility and avoid blinding others, contributing to a safer driving environment for everyone.