What is a Halogen Lamp?
"A halogen lamp (also called tungsten-halogen lamp, quartz-halogen lamp, or quartz-iodine lamp) is an incandescent lamp wherein a tungsten filament is sealed into a small transparent envelope filled with a halogen gas such as iodine or bromine. The halogen lamp can operate its filament at a higher temperature than in a standard vacuum or inert-gas filled lamp, without loss of operating life. This gives it a slightly higher efficiency (10-20%) than standard incandescent lamps. It gives a bright yellow light that is considered by many to be the nearest to daylight from any lamp.
A typical halogen lamp is designed to run for about 2000 hours, twice as long as a typical incandescent lamp."
Text from en.wikipedia.org