When used as a noun, any range of values between a minimum and maximum amount. For example, a gray scale is a series of progressively darker gray values, beginning at white and ending at black.
When used as a verb, scale means to express a quantity in other units, with the new quantity being in some ratio to the original quantity. For example, a model that has been scaled (or a "scale model") can be measured in units (such as inches) which are more easily represented than the original units (such as feet, yards, or miles). The scale of miles found on maps is an example of this; a certain number of miles is "scaled" down to a certain number of inches, so that large land areas can be accurately represented on convenient size paper.
In imaging, scale means to resize an image—either enlarging or reducing it by some amount (called a scale factor)—to fit in a predetermined area, accomplished either photographically or digitally.
Computer PostScript fonts are also scaled; typically, the computer information includes the outline for a particular typeface at only one size. To achieve all other desired sizes, the computer recalculates the formula describing the structure of the characters, allowing it to be cleanly printed at the new size. Other graphic images are also scaled in a similar manner.
The term scale also refers to a paper defect characterized by a slightly discolored, highly glossy blotch on the paper surface, caused by dry particles of paper coating embedded into the paper during calendering.