The relative thickness or blackness of individual characters and their parts. See also typeface weight.
The space occupied by a character plus its left and right side spaces. The measurement of this space may be expressed in different ways: in some computer-aided design software and with hand-done artwork, it is typically expressed in millimeters; in other software and in many typesetting devices, it is expressed in relative units. Also known as character width, set width, set, and (in digital and phototypesetting) escapement. See also unit system, width value.
The measurement, in relative units, of a character plus the spaces on either side. Also known as unit value, character width, set width, and total width. (Note that the terms character width and set width are also sometimes used to refer to the actual space the character occupies.) See also unit system, width.
A space used in typography to separate words. In digital and phototypesetting and in desktop publishing, it may have a predefined width or may be user-defined within specified limits to make it appropriate for a particular typeface, point size, line width, or other variable. It is usually modified by the typesetting software in the process of justification.
In hand-set composition with metal type, the metal blocks that were called spaces or spacing material were not usually included in a font of type but were bought by weight. The height of spaces was less than type height or the height-to-paper, that is, less than the level of the typeface characters themselves, so that the spaces would not print. Spaces included most of the fixed spaces now in use and a variety of hair spaces made of type metal, brass, or copper. Small pieces of paper were also sometimes inserted. In metal type for linecasting, most of the same fixed spaces were used as well as metal space bands that were available in standard widths.