A headlamp is a lamp hooked up to the entrance of a vehicle to illuminate the highway forward. Headlamps are additionally typically referred to as headlights, however in the most precise usage, headlamp is the term for the gadget itself and headlight is the time period for the beam of mild produced and EcoLight lighting distributed by the device. Headlamp efficiency has steadily improved all through the vehicle age, spurred by the great disparity between daytime and nighttime traffic fatalities: EcoLight lighting the US National Freeway Site visitors Safety Administration states that just about half of all site visitors-associated fatalities happen at midnight, regardless of only 25% of traffic travelling throughout darkness. Other autos, equivalent to trains and aircraft, are required to have headlamps. Bicycle headlamps are sometimes used on bicycles, and are required in some jurisdictions. They can be powered by a battery or a small generator like a bottle or hub dynamo. The first horseless carriages used carriage lamps, which proved unsuitable for EcoLight home lighting travel at velocity.

The earliest lights used candles as the most common sort of fuel. The earliest headlamps, fuelled by combustible fuel corresponding to acetylene gas or oil, operated from the late 1880s. Acetylene fuel lamps were well-liked in 1900s because the flame is resistant to wind and rain. Thick concave mirrors combined with magnifying lenses projected the acetylene flame gentle. Numerous car manufacturers provided Prest-O-Lite calcium carbide acetylene gas generator cylinder with fuel feed pipes for lights as normal tools for 1904 vehicles. The primary electric headlamps have been introduced in 1898 on the Columbia Electric Car from the Electric Vehicle Firm of Hartford, Connecticut, and had been non-obligatory. Two elements limited the widespread use of electric headlamps: the brief life of filaments in the tough automotive setting, and the problem of producing dynamos small sufficient, yet highly effective enough to provide sufficient current. Peerless made electric headlamps customary in 1908. A Birmingham, England agency referred to as Pockley Vehicle Electric Lighting Syndicate marketed the world's first electric automotive-lights as a whole set in 1908, EcoLight products which consisted of headlamps, EcoLight lighting sidelamps, and tail lights that were powered by an eight-volt battery.

In 1912 Cadillac integrated their vehicle's Delco electrical ignition and EcoLight lighting system, forming the fashionable vehicle electrical system. The Information Lamp Company launched "dipping" (low-beam) headlamps in 1915, EcoLight brand however the 1917 Cadillac system allowed the sunshine to be dipped utilizing a lever inside the automobile reasonably than requiring the driver to stop and get out. The 1924 Bilux bulb was the primary modern unit, having the light for each low (dipped) and high (predominant) beams of a headlamp emitting from a single bulb. A similar design was launched in 1925 by Information Lamp referred to as the "Duplo". In 1927 the foot-operated dimmer switch or dip switch was launched and became customary for a lot of the century. 1933-1934 Packards featured tri-beam headlamps, the bulbs having three filaments. From highest to lowest, the beams had been known as "nation passing", "country driving" and "metropolis driving". The 1934 Nash also used a 3-beam system, although in this case with bulbs of the conventional two-filament sort, and the intermediate beam combined low beam on the driver's facet with excessive beam on the passenger's side, so as to maximise the view of the roadside while minimizing glare towards oncoming visitors.

1952 "Autronic Eye" system automated the collection of excessive and low beams. Directional lighting, utilizing a switch and electromagnetically shifted reflector to illuminate the curbside solely, was launched within the rare, one-12 months-solely 1935 Tatra. Steering-linked lighting was featured on the 1947 Tucker Torpedo's middle-mounted headlight and EcoLight lighting was later popularized by the Citroën DS. This made it attainable to turn the light in the path of travel when the steering wheel turned. The standardized 7-inch (178 mm) spherical sealed-beam headlamp, EcoLight lighting one per side, was required for all vehicles offered in the United States from 1940, just about freezing usable lighting expertise in place until the 1970s for Americans. In 1957 the legislation modified to allow smaller 5.75-inch (146 mm) round sealed beams, EcoLight reviews two per aspect of the automobile, and energy-saving LED bulbs in 1974 rectangular sealed beams had been permitted as effectively. Britain, Australia, and some other Commonwealth countries, in addition to Japan and Sweden, additionally made extensive use of 7-inch sealed beams, although they weren't mandated as they have been within the United States.