Lithography

The invention of photography in the twentieth century spurred the development of a new lithographic process called photolithography. In this method, the printer shines a bright light through a photo negative onto a thin plate coated with light-sensitive chemicals. The areas of the plate struck by the light harden into a reproduced image, serving the same function as the grease design in early lithography. Today, lithographic processes are the most widely-used printing methods.