Each initial that follows the name of a ribbon made for an ID card machine stands for a substance that an ID card manufacturer has deposited onto one of ribbon’s panels.

"Y”, “M”, and “C” stand for yellow, magenta, and cyan: the three colors from which all other colors appearing on ID cards are made. On dye sublimation ID card printer ribbons, each of these colors takes the form of a dye on its own panel.

"K” stands for black. The black bar codes and text that ID cards carry are produced when an ID badge printer melts special resin-based black ink carried on this “K” panel.

"O” stands for “overcoat”. This panel deposits a protective, clear layer on top of the colors that the ribbon’s other panels have already left behind.

The ID printer ribbon designated “YMCKOK” is designed for those making employee ID badges and security ID badges who want color on the front of ID badges, but only black on their back. Rather than requiring a duplex ID badge printer to cycle through – and waste - another three color panels, to once again get to black, these ribbons tack the extra black panel on to the end of the sequence.

Other initials ID card printer ribbon initials stand for rarer substances. “Uv” means “ultraviolet”; images printed onto ID badges using this panel appear only when the ID card is passed under special ultraviolet lights. “F” refers to a panel that transfers fluorescent dye onto ID cards.