How can I determine if a headlight bulb is blown?

To determine if a headlight bulb is blown, visually inspect the bulb for any signs of damage or discoloration. If the filament inside the bulb is broken or appears blackened, the bulb is likely blown. Additionally, you can test the bulb by turning on the headlights and checking if the affected headlight does not illuminate. If the headlight does not turn on, it may indicate a blown bulb.