A Printing Machine is a sophisticated piece of high-precision industrial machinery created to generate printed material quickly and affordably. Commercial printing presses are available that use a variety of printing processes, although offset lithography is the most used one. Printing Machines are often made in sheet-fed or web-fed designs, depending on whether they print on single sheets of paper or other material or long webs of paper or other material that are supplied on big reels. A 'full size' sheet feed offset press prints on roughly 700 mm × 1000 mm-sized sheets (about 28 inches x 40 inches).
Offset Printing Machine that print on sheets that are half as large or a quarter as large are also popular and known as "half size" and "quarter size" presses. Each ink colour is printed separately in a tower on an offset Printing Machine. In some presses with up to 12 towers, the sheet is printed in 6 colours on one side, flipped over in a device called a perfector, and then printed in 6 colours on the other side. The four main colours produced are typically black plus the three subtractive primary colours (cyan, magenta, and yellow). Spot colours, which are intensely saturated hues that go outside the range of colours that can be generated with subtractive primaries, are frequently utilised as logo colours or to create stunning artistic effects. Other inks are typically added to these four primary colours.
