Antibody engineering is a methodological approach within molecular biology and immunology focused on the rational design, modification, and optimization of antibody molecules. It investigates the relationship between antibody structure and desired biological functions, employing techniques such as recombinant DNA technology, protein expression systems, and computational modeling to create antibodies with enhanced specificity, affinity, effector functions, half-life, and manufacturability. Its significance lies in enabling the development of next-generation antibodies for therapeutic, diagnostic, and research applications with improved efficacy and safety profiles.