The offset printer is fundamentally based on the same principle of lithography (there is also a technique or dry offset much less common that uses arrays in relief).
It is therefore an indirect printing: this means that printing does not take place, as in the other types of printing direct type, directly transferring the ink from the plate (matrix) to the support, but occurs with the ink that is returned from the plate lithographic to the blanket, and from this to the paper.
