A fluorescent light bulb is a type of electric light that uses a gas-filled tube to produce light. Inside the bulb, a small amount of mercury vapor is excited by an electric current, which emits ultraviolet light. This ultraviolet light then interacts with a phosphor coating on the inside of the bulb, creating visible light. Fluorescent bulbs are known for their energy efficiency and longer lifespan compared to traditional incandescent bulbs. They are commonly used in homes, offices, and commercial spaces. These bulbs come in various shapes and sizes, making them versatile for different lighting needs.