A street light, light pole, lamp pole, lamppost, street lamp, light standard, or lamp standard is a raised source of light on the edge of a road or path. Similar lights may be found on a railway platform. When urban electric power distribution became ubiquitous in developed countries in the 20th century, lights for urban streets followed, or sometimes led.
Many lamps have light-sensitive photocells that activate the lamp automatically when needed, at times when there is little-to-no ambient light, such as at dusk, dawn, or at the onset of dark weather conditions. This function in older lighting systems could be performed with the aid of a solar dial. Many street light systems are being connected underground instead of wiring from one utility post to another. Street lights are an important source of public security lighting intended to reduce crime.
Oil lamp and Gas lighting
Early lamps were used in the Ancient Greek and Ancient Roman civilizations, where light primarily served the purpose of security, both to protect the wanderer from tripping on the path over something or keeping potential robbers at bay. At that time, oil lamps were used predominantly, as they provided a long-lasting and moderate flame. A slave responsible for lighting the oil lamps in front of Roman villas was called a lanternarius.
However, denizens of Beijing could be the first to use "fixed position lighting" (unlike hand-carried torches and lamps), as far back as 500 B.C., utilizing hollow bamboo as a piping and naturally occurring gas vents to create kind of street lamps.
At the verge of the Middle Ages, cities like Antioch had their streets lit, a practice which continued across the Arab Empire, long before Europe. In the words of Edwin Heathcote: "Romans illuminated the streets with oil lamps, and cities from Baghdad to Cordoba were similarly lit when most of Europe was living in what it is now rather unfashionable to call the Dark Ages but which were, from the point of view of street lighting, exactly that.