The frontal sinus is a pair of air-filled cavities located in the forehead region, just above the eyes. These sinuses are part of the paranasal sinuses, which also include the maxillary, ethmoid, and sphenoid sinuses. They are lined with mucous membranes that help to humidify and filter the air we breathe, as well as produce mucus to trap pathogens and debris. The primary function of the frontal sinus is to reduce the weight of the skull and enhance voice resonance. Additionally, they play a role in protecting the brain from trauma by acting as a cushion. Inflammation or infection of the frontal sinus can lead to conditions such as sinusitis, causing symptoms like pain, pressure, and congestion.