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We breathe about 30,000 times a day. As we continuously inhale and exhale, oxygen needed to our body moves to the lungs, while carbon dioxide is released from the body. The pathway through which air travels is commonly referred to as the airway. The airway, from the larynx to the bronchi, plays a more critical role in breathing than the lungs. Even if the lungs are healthy, conditions like asthma or chronic obstructive pulmonary disease (COPD) may cause breathing difficulties, making even simple daily activities challenging. Around the neck, there are nerve bundles connecting the brain to the entire body, important blood vessels carrying blood from the heart to the head, the esophagus that transports food to the stomach, and the airway as a passageway for air. The airway can be broadly divided into three main parts: the larynx, trachea, and bronchi. The larynx, where the airway begins, is composed of cartilage, making it relatively firm. The larynx has a flap called the epiglottis, preventing food from entering the airway. Inside the larynx, there are vocal cords made of thin membranes that vibrate as air passes through, producing the voice. The end of the trachea divides into the left and right bronchi, which connect to the lungs, and branch out into multiple bronchioles resembling tree branches. These bronchioles eventually connect to the alveoli, where gases like oxygen and carbon dioxide are exchanged. The trachea, located in front of the esophagus, has a unique structure to maintain airflow. The trachea, connected to the larynx, is about 10 cm long, about the size of a thumb, and shaped like a tube. The trachea is composed of around 20 horseshoe-shaped cartilages stacked in layers. These cartilages, during activities like moving the neck or eating, keep the trachea open and maintain its shape, preventing it from being compressed. The posterior wall of the trachea has no cartilage and is strongly connected to the esophagus. Occasionally, if this connection is damaged or inflamed, a perforation may occur. The airway serves as a passage for air and also protects the lungs from foreign particles, such as dry air or dust, entering from the outside. The mucous membrane within the airway is covered by a sticky mucus and contains tiny, hair-like structures called cilia. The mucus inside the airway traps foreign particles that enter during inhalation, preventing them from reaching the lungs. Foreign particles, such as dust, attached to the mucus are moved out of the airway by the cilia. When foreign particles mix with mucus and lymph fluid, they become sputum, which may trigger coughing when it irritates the airway mucosa. While coughing is often misunderstood as pathological, it is actually a normal defense mechanism of the body to clear the airway of foreign particles or secretions. Below the mucous membrane are tracheal glands and lymph nodes. The tracheal glands secrete mucus to keep the air entering the airway at adequate humidity, while the tracheal lymph nodes monitor the trachea and bronchi for abnormalities. Due to exposure to polluted air, including smoke, cigarette smoke, and dust, patients suffering from respiratory conditions such as bronchial asthma, bronchiectasis, and COPD are steadily increasing. These respiratory conditions typically present with symptoms such as coughing, sputum, and shortness of breath, but accurate differential diagnosis is necessary as the causes and treatments vary by disease. If symptoms like coughing and sputum persist for more than two weeks or are accompanied by shortness of breath, it is crucial to quit smoking and take quick action before it progresses to a more serious condition.