Neon tubes are glass tubes filled with gas, typically neon, that emit light when an electric current passes through them. These tubes are often bent into various shapes and are commonly used for decorative lighting, signs, and art. The gas inside glows brightly, creating vibrant colors, especially in the case of neon. In addition to neon, other gases like argon and krypton can be used in these tubes to produce different colors. The tubes are often coated with phosphor to enhance the brightness and variety of colors. Neon tubes have become iconic in urban environments, adding a unique aesthetic to nightlife and advertising.