The primary purpose of the printing industry is to create and
manufacture products that communicate visually. The printing process
known as offset lithography dates back over 200 years. In offset
printing, the image on the plate is transferred to the rubber blanket on
the blanket cylinder. The rubber blanket then transfers or offsets, the
image to the paper. Offset lithography is also called planography
because the printing areas are on the same plane as the surface of the
printing plate. Offset lithography is based on the principle that water
and grease do not readily mix. During printing, the image areas accept
only the lithographic ink, and the nonimage areas accept only water.
There have been many technological advancements within offset
lithography from digital presses to CTP (Computer to Plate) technology.
Before a beginner learns about the new advancements, it is important
that he or she learn the basic pre-press and press techniques used in
the past. LITHOS was designed to help beginner Lithography students go
through the pre-press, press, and post-press steps for a basic one-color
design.