Fluorescent lights are among the most popular lighting system used worldwide. Fluorescent tubes/lamps are filled with mercury vapor. They use electric charge to excite mercury atoms in order to produce ultra violet light. A glow starter or commonly known as starter is used in the tube light circuit to provide an initial current to filaments of the tube light. When the switch is pressed current cannot pass through the tube initially because the gas inside it is not ionized and hence the tube light circuit behaves as open circuit. Once the gas is ionized, it will provide a conduction path for the current to flow. In order to ionize the gas, an initial high current is required for a short period across the filaments of the main tube. That is what a starter does.