Pulmonary infections encompass a diverse group of Respiratory Tract Infections that can affect the lungs and associated structures. Common pathogens include bacteria, viruses, fungi, and atypical microorganisms. Bacterial Pneumonia is a prevalent pulmonary infection, with Streptococcus pneumoniae being a leading cause, particularly in community-acquired cases. Other bacterial culprits include Haemophilus influenzae, Mycoplasma pneumoniae, and Legionella pneumophila. Viral respiratory infections, such as influenza viruses, Respiratory Syncytial Virus (RSV), and adenoviruses, also contribute significantly to pulmonary infections, often manifesting as bronchitis or pneumonia. In immunocompromised individuals, opportunistic Fungal Infections like Aspergillus or Pneumocystis jirovecii may cause severe pulmonary complications. Tuberculosis, caused by Mycobacterium tuberculosis, is a globally significant pulmonary infection, often characterized by chronic granulomatous inflammation in the lungs.