Gas discharge refers to the process where gas molecules become ionized and conduct electricity. This occurs when a high voltage is applied across a gas, causing the gas to emit light and produce charged particles. Common examples of gas discharge can be seen in neon signs and fluorescent lamps, where the gas inside glows when electricity passes through it. In a gas discharge tube, the gas is typically at low pressure, allowing for easier ionization. The emitted light can vary in color depending on the type of gas used, such as neon for red or argon for blue. This phenomenon is widely utilized in various lighting and display technologies.