Camera-ready art consisting of typeset text, heads, line art or other illustration matter, and other page elements pasted-up into the proper position and ready for the making of negatives or plates. Mechanical also refers to the rigid paper or paperboard on which these materials are pasted-up. Mechanicals are increasingly being generated digitally, however.
The term mechanical is also used to refer to any process or function performed by a machine, in contrast to "manual," "chemical," or "electronic." (In some cases, though, mechanical does refer to a process performed manually.)