Indicating Light: Typically an LED used to show the status of a device or circuit. Connect the anode (longer lead) through a current-limiting resistor (e.g., 220Ω–1kΩ) to a voltage source, and the cathode (shorter lead) to ground. Ensure correct polarity and voltage level (usually 3.3V or 5V). For panel indication, use appropriate color (e.g., red for power, green for ready).