How is argon used in florescent lighting?

Argon is used in fluorescent lighting as an inert gas that helps create a low-pressure environment within the lamp. When an electric current passes through the argon gas, it produces a faint blue light. This blue light then excites a phosphor coating on the inside of the bulb, which emits visible light. Additionally, argon helps to prevent the oxidation of the filament, enhancing the lamp's longevity and performance.