A Pulmonary Function Test (PFT) is a group of tests that measure how well the lungs are working. These tests assess lung volume, capacity, and the flow of air in and out of the lungs. They help diagnose conditions like asthma, chronic obstructive pulmonary disease (COPD), and other respiratory issues. During a PFT, patients may be asked to breathe into a device called a spirometer. This device records the amount of air inhaled and exhaled, providing valuable information about lung function. The results can guide doctors in determining the best treatment options for patients with lung-related problems.