In the age of incandescent bulbs, people chose a lightbulb based on the number of watts it produced. Today, lighting choices have expanded, and people shop according to lumens, a unit of brightness. Look for the Lighting Facts label when shopping for bulbs.
Incandescent bulbs work by heating a tungsgten filament to 4,000 degrees Fahrenheit (2,200 degrees Celsius).
Compact Fluorescent bulbs work by heating a gas that produces ultraviolet light. The coating inside the bulb converts the invisible ultraviolet light into visible light.
LED bulbs use solid-state light-emitting diodes.
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