Printing, name used for several processes by which words, pictures, or designs are reproduced on paper, fabrics, metal, or other suitable materials. These processes, sometimes called the graphic arts, consist essentially of making numerous identical reproductions of an original by mechanical means, and the printed book has thus been called the first mass product.

The history of printing, which by its very nature is considered to be the most thoroughly documented of any history, practically identical with that of relief, or letterpress, printing (printing from a raised surface). Historically speaking, the bulk of all printing has been produced by this entirely mechanical method. Modern printing techniques, however, increasingly rely on photomechanical and chemical processes. In recent years computer technology has become important and adds up to the complexity of the printing procedures.

The various printing techniques were long been observed by ancient communities. In fact in the application of signet stones is possibly the earliest known form of printing. Used in ancient times in Babylonia and elsewhere, apparently both as substitutes for signatures and as religious symbols, the devices consisted of seals and stamps for making impressions in clay or of stones with designs cut or scratched on the surface. In the east, Chinese favorable invention made available the use of paper. However, in the west movable metal type was first cast with printing paper on the middle and use oil-based inks.

Today, the machine is used to transmit the inks from a printing plate to the printed page called a press. The first printing presses, such as those of the 16th century and earlier, were screw-type presses designed primarily to bring pressure on the printing form, which was placed face up in a flat bed. The paper, generally dampened, was pressed against the type by the movable surface, or platen. Then the next thing was the introduction of iron as the substitute for the screws. In 19th century improvements included the development of the steam-powered press; the cylinder press, which uses a revolving cylinder to press the paper against a flat printing form; the rotary press, in which both the paper and a curved printing plate are carried on cylinders; and a practical perfecting press, which prints on both sides of a sheet of paper simultaneously.

The modern printing process is now largely controlled by computers. Printed images can be created from data gathered from images either scanned into a computer or obtained from a database. Once the images are in the correct format, image carriers are created which are then either printed from directly or fed into the printing machine