A streetlight, 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 streetlight systems are being connected underground instead of wiring from one utility post to another. Street lights are an important source of publicsecuritylighting intended to reduce crime.