Headlights are built into every car, truck, and other kind of vehicle on the road. What many people may not realize is that there are various headlight types available, and not just one single form of lamp that comes standard with each car. Headlight types include halogen and incandescent lights, xenon lights, fog lights, and pencil beams. No matter what type of headlight is being used, it provides the best kind of automotive night vision there is. If turned on as they should be when they should be, these lights allow you to see other vehicles, pedestrians and obstacles on the road whether it is dark or the weather is affecting visibility.
The most basic form of headlight is an incandescent light. This bulb has a filament like a regular light bulb. It is just built bigger than one you would fit into a lamp at home. Incandescent headlights have been used for more than 100 years and glow when heat is added to the tungsten filament. They are widely available for automotive use and can be replaced easily and relatively inexpensively.
Halogen lights also have a tungsten filament, but they are filled with halogen gas that causes the evaporated tungsten to condense back onto the filament. Therefore, the filament is not worn down as quickly and the bulb lasts longer. A xenon light operates in a similar way, but this gas also makes the light shine brighter, all from inside a sealed bulb where the light is ignited by an electrical charge. The glare can be quite intense if the bulb is not installed properly, but the higher light output and less drain on the vehicle's battery is appealing to many car owners.
A fog light is another form of headlight that focuses the light beam so it does not reflect off of fog as well as rain or snow, therefore improving the line of sight for drivers in inclement weather and reducing the risk of traffic accidents. In addition to standard driving lights, or high-beam lights that offer an adequate visibility range of 800 feet, there are also long-range, or pencil beam lights. These can illuminate a field of view up to 2,000 feet ahead of the vehicle. They are so bright that they are listed as illegal in some states. Regardless of the type of headlight, it must be adjusted at the correct angle so it doesn’t distract other drivers.