K:  one of the four colors of the CMYK printing process, black in color. Also referred to as the Key color.

printed lines showing where to trim a printed sheet

all the activities required to prepare a press for printing

to keep each piece separate or independent

the material to be printed on

distinctive design created in paper at the time of manufacture that can be easily seen by holding the paper up to a light

using the same plate and same guide, printing one side of a sheet, and flipping it from gripper to tail to print on the back of the sheet. Similar to perfecting but 2 passes.

using the same plate and common guide, printing one side of a sheet, and flipping it from left to right to print on the back of the sheet