M Abbreviation for mega, that is commonly used to mean one million. Megabyte. In computer terminology, however, M refers to the number 1,048,576, and is used to specify the amount of storage available on a disk or in memory. Also, abbreviation for quantity of 1,000.

Machine coated Paper that is coated on one or two sides on a paper machine.

Machine direction Same as grain direction in paper.

Magenta Hue of a subtractive primary and a four-color process ink. It reflects or transmits blue and red light and absorbs green light.

Magnetic storage Any disk, film, tape, drum, or core that is used to store digital information.

Makeover A plate that is remade.

Makeready All work done to set up a press for printing. Happens after prepress. After proofs are checked and plates are made, the printing plates are mounted and the press brought into register: this, my friend, is makeready.

Mask In color separation photography, an intermediate photographic negative or positive used in color correction. In offset lithography, opaque material used to protect open or selected areas of a printing plate during exposure.

Master A plate for a duplicating machine.

Matte finish Dull paper finish without gloss or lustre.

Measure In composition, the width of a line of type, usually expressed in picas. Also called line length or column width.

Mechanical A term for a camera-ready pasteup of artwork. It includes type, photos, line art, etc., all on one piece of artboard. It is photographed in a graphic arts camera and the resultant film is stripped into flats for platemaking.

Mechanical pulp In papermaking, groundwood pulp produced by mechanically grinding logs or wood chips. It is used mainly for newsprint and as an ingredient of base stock for lower grade publication papers.

Megabyte (Mbyte, MB, Meg, or M) One million character codes on the computer. One million bytes or characters, often written MB or Mbyte. A unit of measurement equal to 1,024 kilobytes, or 1,048,576 bytes.

Megahertz (MHz) Frequency equal to one million cycles per second. Measures bandwidth or analog electronic signals.

Menu A method for selecting alternative functions displayed as a list on a workstation screen. Selection via mouse, key, or sequence of keys. Menus may be contextual and change based on the content or function selected.

Metric system A decimal system adopted by most countries for solid, liquid, and distance measurements. See grammage.

Middletones The tonal range between highlights and shadows of a photograph or reproduction.

Moiré In color process printing, the undesirable screen pattern caused by incorrect screen angles for printed colors of overprinting halftones.

Monitor A video screen or display on a workstation or any other electronic device or system.

Montage In artwork, several photographs combined to form a composite illustration.

Mottle The spotty or uneven appearance of printing, mostly in solid areas.

Mouse A hand-held device that moves the cursor on a workstation by moving the device on a flat surface.

Mullen tester A machine for testing the bursting strength of paper.