Science and technology in the United States finish. For example, the British engineer Joseph Swan built an incandescent electric lamp in 1860, almost 20 years before Edison. But Edison's light bulbs lasted much longer than Swan's, and they could be turned on and off individually, while Swan's bulbs could be used only in a system where several lights were turned on or off at the same time. Edison followed up his improvement of the light bulb with the development of electrical generating systems. Within 30 years, his inventions had introduced electric lighting into millions of homes. Another landmark application of scientific ideas to practical uses was the
Compact fluorescent lamp Compact fluorescent lamp A compact fluorescent lamp (CFL), also called compact fluorescent light, energy-saving light, and compact fluorescent tube, is a fluorescent lamp designed to replace an incandescent light bulb; some types fit into light fixtures designed for incandescent bulbs. The lamps use a tube which is curved or folded to fit into the space of an incandescent bulb, and a compact electronic ballast in the base of the lamp. Compared to general-service incandescent lamps giving the same amount of visible light, CFLs use one-fifth to one-third the electric power, and last eight to fifteen times longer. A CFL has