Sky Ladder,” a pyrotechnic artwork by Cai Guoqiang, a Chinese contemporary artist currently living and working in New York City. Cai is best known for using gunpowder in his spectacular works.
Pyrotechnic is the science of using materials capable of undergoing self-contained and self-sustained exothermic chemical reactions for the production of heat, light, gas, smoke and/or sound. Pyrotechnics include not only the manufacture of fireworks but items such as safety matches, oxygen candles, explosive bolts and fasteners, components of the automotive airbag and gas pressure blasting i mining, quarrying and demolition.
Source: Youtube User Teetoo, Google