In the 20th century, the development of automobiles, rolling bearings, miniature motors, and the sewing machine industry spurred the emergence of automated production lines in mechanical manufacturing. The earliest form was the combined machine tool automatic line. Before the 1920s, production and automated lines first appeared in the automotive industry, later evolving into fully automated systems. Following World War II, industrialized nations saw a sharp rise in the adoption of automated lines across the mechanical manufacturing sector, significantly enhancing production efficiency and precision.