Molecular immunology is the study of the immune system at the molecular level, focusing on the interactions and functions of immune molecules such as antibodies, antigens, cytokines, and receptors. It examines how immune cells recognize and respond to pathogens, how signaling pathways regulate immune responses, and how genetic and molecular mechanisms influence immunity. This field also explores the molecular basis of immune-related diseases such as autoimmunity, allergies, immunodeficiencies, and cancer. Techniques like PCR, ELISA, flow cytometry, and monoclonal antibody production are widely used in molecular immunology research. Understanding these molecular processes is essential for developing vaccines, immunotherapies, and diagnostic tools. Molecular immunology plays a crucial role in advancing treatments for infectious diseases, inflammatory conditions, and immune system disorders by linking basic science with clinical applications.