Standard incandescents are very inefficient. About 90% of the energy given off is in the form of wasted heat. They yield about 13 lumens/watt and have a life of 750-1000 hours.
Sir Joseph Swann invented them in the 1870s; although most Americans credit Thomas Edison [6]. Watch for improved versions using deposited carbon nanotube filaments by 2009. This may not matter since many governments are banning tungsten bulbs. Australia is targeting 2010, the USA 2012-2014.
== Application ==