Street lights, also known as light poles, lampposts, and street lamps, are raised public fixtures that provide illumination on the edge of a road or path when light is needed. Light-sensitive photocells are activated automatically at dusk, dawn, or at the start of dark weather. Street lights were first used in the city of Antioch from the 4th century to protect pedestrians from tripping on a path. The first widespread system of street lighting employed coal gas as the predominant source of fuel. Today, new street lighting technologies such as LED and high-intensity discharge lamps are used as beacon lights, roadway lights, and cycle path lights.
The height of a street light tends to vary from what kind of area, type of street, type of fixture, owner, and lighting conditions. Street light poles are typically 8 to 50 feet (2.4 – 15.2 m) tall. Street poles taller than 50 feet (15.2 m) are considered a high-mast.
Some cities and suburbs maintain their own streetlights through their department of transportation, and pay for the energy they consume. Often utilities are the owners of the streetlights and charge the town or city a monthly rate that includes the street light, maintenance, and total energy use.
Electric street lights were first implemented in Paris in 1878. By 1890, more than 130,000 electric street lights were installed in the United States. These first versions of the modern street lights offered harsh lighting, and did not last a very long time. They were later replaced with incandescent street lights.