1.   Based on an ordinary street lamp, it introduced street smarts into the modern home and office.

2.   Like ordinary lamps, halogen is an incandescent, meaning that it passes electrons through a tungsten filament, which gives off light and heat.

3.   Over hundreds of hours, the filament in an ordinary lamp evaporates into the gas inside the bulb.

4.   The nitrogen of ordinary lamps is at normal atmospheric pressure, allowing the use of ordinary glass.