A headlamp is a lamp connected to the front of a automobile to illuminate the street ahead. Headlamps are also often known as headlights, but in essentially the most exact usage, headlamp is the time period for the system itself and headlight is the term for EcoLight the beam of light produced and distributed by the device. Headlamp performance has steadily improved throughout the car age, spurred by the good disparity between daytime and nighttime site visitors fatalities: the US National Highway Traffic Safety Administration states that just about half of all visitors-associated fatalities occur in the dead of night, despite only 25% of site visitors travelling during darkness. Other vehicles, akin to trains and aircraft, are required to have headlamps. Bicycle headlamps are often 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 journey at pace.

The earliest lights used candles as the most typical kind of fuel. The earliest headlamps, EcoLight fuelled by combustible gasoline akin to acetylene fuel or oil, operated from the late 1880s. Acetylene gasoline lamps were widespread in 1900s as a result of the flame is resistant to wind and rain. Thick concave mirrors mixed with magnifying lenses projected the acetylene flame mild. A lot of automobile manufacturers provided Prest-O-Lite calcium carbide acetylene gas generator cylinder with gasoline feed pipes for lights as standard tools for 1904 automobiles. The first electric headlamps were launched in 1898 on the Columbia Electric Automotive from the Electric Car Firm of Hartford, Connecticut, and had been non-obligatory. Two components restricted the widespread use of electric headlamps: the short life of filaments in the cruel automotive atmosphere, and the issue of producing dynamos small sufficient, but powerful sufficient to supply sufficient current. Peerless made electric headlamps commonplace in 1908. A Birmingham, England EcoLight firm referred to as Pockley Vehicle Electric Lighting Syndicate marketed the world's first electric automobile-lights as an entire set in 1908, reduce energy consumption which consisted of headlamps, sidelamps, and tail lights that had been powered by an eight-volt battery.

In 1912 Cadillac built-in their automobile's Delco electrical ignition and lighting system, forming the fashionable automobile electrical system. The Guide Lamp Firm introduced "dipping" (low-beam) headlamps in 1915, but the 1917 Cadillac system allowed the sunshine to be dipped utilizing a lever inside the automobile fairly than requiring the driver to cease and get out. The 1924 Bilux bulb was the primary fashionable unit, having the sunshine for each low (dipped) and EcoLight energy high (principal) beams of a headlamp emitting from a single bulb. The same design was introduced in 1925 by Information Lamp known as the "Duplo". In 1927 the foot-operated dimmer swap or dip switch was introduced and grew to become normal for much of the century. 1933-1934 Packards featured tri-beam headlamps, the bulbs having three filaments. From highest to lowest, the beams have been known as "nation passing", "country driving" and "city driving". The 1934 Nash additionally used a 3-beam system, although on this case with bulbs of the typical two-filament type, EcoLight solutions and the intermediate beam combined low beam on the driver's aspect with excessive beam on the passenger's facet, so as to maximise the view of the roadside whereas minimizing glare towards oncoming site visitors.

1952 "Autronic Eye" system automated the selection of high and EcoLight low beams. Directional lighting, utilizing a switch and electromagnetically shifted reflector dimmable LED bulbs to illuminate the curbside only, was introduced within the uncommon, one-year-only 1935 Tatra. Steering-linked lighting was featured on the 1947 Tucker Torpedo's center-mounted headlight and was later popularized by the Citroën DS. This made it potential to turn the sunshine within the course of travel when the steering wheel turned. The standardized 7-inch (178 mm) spherical sealed-beam headlamp, one per side, was required for all automobiles sold in the United States from 1940, just about freezing usable lighting know-how in place until the 1970s for People. In 1957 the regulation changed to permit smaller 5.75-inch (146 mm) spherical sealed beams, two per facet of the vehicle, and EcoLight in 1974 rectangular sealed beams had been permitted as nicely. Britain, Australia, and another Commonwealth international locations, in addition to Japan and Sweden, additionally made extensive use of 7-inch sealed beams, although they were not mandated as they have been in the United States.