Lung compliance refers to the ability of the lungs to stretch and expand during breathing. It measures how easily the lungs can inflate when air is drawn in. High lung compliance means the lungs can expand easily, while low compliance indicates stiffness, making it harder to breathe. Factors affecting lung compliance include lung diseases like pulmonary fibrosis, which can make the lungs stiffer, and conditions like asthma, which can increase compliance temporarily. Understanding lung compliance is important for assessing respiratory health and guiding treatment in patients with breathing difficulties.