Total lung capacity (TLC) is the maximum amount of air that the lungs can hold. It includes several components: tidal volume, inspiratory reserve volume, expiratory reserve volume, and residual volume. TLC is an important measure of lung health and function, often assessed through pulmonary function tests. TLC varies based on factors such as age, gender, body size, and physical fitness. For example, adult males typically have a higher TLC than adult females. Understanding TLC helps healthcare professionals diagnose and monitor respiratory conditions, ensuring effective treatment and management of lung health.