Within the first century of printing two more congenial methods become available - engraving and etching. Both are described as intaglio ('cut in' in Italian) because they excavate grooves in the surface of a copper plate. In engraving, slivers of metal are gouged out with a sharp tool (the burin). In etching, acid is used to eat away the copper along lines drawn through a coating of wax (which protects the rest of the metal surface).
A copper plate created by either of these methods will produce a finer and more delicate print than a wood block. The disadvantage is that intaglio prints require a different kind of press, where the inked copper plate and a sheet of paper are together passed between two rollers, like a great mangle. Intense pressure forces the paper into the grooves of the metal to pick out the ink.
Images of this kind from copper plates are separate from the text. They have to be bound into the finished book, acquiring the name of 'plates'. From the late 16th century a volume with plates becomes the standard form of illustrated book.
From incunabula to mass communication: 1457 - 1525
In the first half-century of European printing the book rapidly displaces the the manuscript of earlier generations, providing equal elegance at less cost. Printed books of the 15th century are known as incunabula (Latin for the 'cradle' of printing). Though very rare now, incunabula were surprisingly numerous then; 1700 presses in some 300 towns are estimated to have produced about 15 million volumes by 1500.
Even in their own time these incunabula are special and expensive objects. But printing has another trick up its sleeve - in the long run one which is much more significant.
The profusion of presses in Europe by the early 16th century means that the machinery is in place for a different and entirely new form of production - the rapid printing of pamphlets, or even single sheets, which can be used in a war of propaganda.
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