Lithography is a major stepping stone in the history of printing. While modern high-resolution and 3D printing technologies seem new, some of the basic ideas are centuries old.
Alois Senefelder produced the very first lithography print in 1796. The printing process uses a smooth stone (at the time, Senefelder used limestone) or metal plate. An image or text is drawn onto the smooth area using wax, oil or fat and is then treated with an acid and gum arabic mixture. The surface would then receive a light application of water, followed by an oil based ink. The oil based ink would be repelled by the water and in turn only stick to the oil, fat or wax of the surface. The information would then be pressed onto the paper. Lithography allowed for the quick production of pamphlets and other written information.
The printing process has remained relatively intact since its initial creation. The lithograph is made up of two different parts known as the negative image and the positive image. The negative part of the image is what retains water and blocks the oil based ink while the positive part of the image is what collects the oil ink and prints onto blank sheets of paper.
Modern lithographic printers no longer rely on limestone but instead sheets of metal for printing, as the metal is more durable and readily available. Slightly flexible aluminum, polyester or paper printing plates are used, and no longer use an oil based ink. Instead a photosensitive emulsion is used. Oil based ink is especially messy and difficult to clean, so the photosensitive emulsion makes it easier to mass produce imagery and text without staining or causing costly errors during the printing process.