This thesis examines the main types of welded joints used in modern engineering and manufacturing. The study provides a detailed classification of welded joints, including butt, lap, corner, edge, and tee joints, analyzing their structural features, mechanical performance, and applications. Special attention is given to how joint design affects stress distribution, weld strength, and overall reliability of welded structures. The paper also discusses modern welding technologies and quality assessment methods that ensure the durability and safety of welded components. Keywords: welded joint, butt joint, lap joint, corner joint, tee joint, edge joint, welding process, mechanical properties, structural design