Pulmonary nodules are small, round or oval-shaped growths in the lung that are less than 3 centimeters in diameter. These nodules are commonly found on chest imaging studies such as chest x-rays or CT scans, and can be caused by a variety of conditions including infections, inflammation, or tumors. Research in this area focuses on diagnosing and determining the significance of pulmonary nodules, as well as identifying the best approaches for monitoring and managing them. This research is important because some nodules can be benign, while others may be indicative of lung cancer or other serious conditions. Treatment decisions often depend on accurately characterizing the nature of the nodule, which can be challenging due to their small size and diverse underlying causes.