Definitions of Terms Used When Describing Fonts

a-space, b-space, c-space -

The a-space is the distance from the left of the character frame to the left edge of the character. The b-space is the width of the character. The c-space is the distance from the right edge of the character to the right of the character frame. Negative values of a and c allow adjacent character frames to overlap. See also character increment, and space default values.
average char width -
The average horizontal distance from the left edge of one character to the left edge of the next. Contrast with max char increment.
baseline -
The line on which the bottom of a character rests, and below which a descender extends.
beak char code point -
The code point of the space or break character. Contrast with default char code point, first char code point, and last char code point.
character increment -
A set of three values (a-space, b-space, and c-space) that define the proportions of a character. The sum of the three values (a+b+c) specifies only one value for the entire character increment. See also font width and space default values.
character rotation -
The angle by which each character is rotated around its own center, increasing clockwise from vertical. Contrast with character slope and inline direction.
character slope -
The angle by which a character is slanted, increasing clockwise from vertical. Contrast with character rotation and inline direction.
default char code point -
The code point of the character to be used if a code point outside the range of a font is passed to an application using that font. Contrast with break char code point, first char code point, and last char code point.
em height -
The maximum distance above the baseline reached by an uppercase symbol. Contrast with x height.
external leading -
The vertical distance from the bottom of one character to the top of the character below it. Contrast with internal leading and max baseline extent.
first char code point -
The code point of the first character. All numbers between the first char code point and the last char code point must represent a character in the font. Contrast with break char code point, default char code point, and last char code point.
fixed spacing -
The same amount of space separates each character. Contrast with proportional spacing.
font weight -
The line-thickness of a character relative to its size. Contrast with font width.
font width -
The relative width of a character to its height; condensed fonts are very narrow while expanded fonts are very wide. See also character increment. Contrast with font weight.
inline direction -
The angle of a line of type, increasing clockwise from horizontal. Contrast with character rotation and character slope.
internal leading -
The vertical distance from the top or bottom of a character to any accent marks that may appear with it. Contrast with external leading.
last char code point -
The code point of the last character. All numbers between the first char code point and the last char code point must represent a character in the font. Contrast with break char code point, default char code point, and first char code point.
lowercase ascent -
The maximum distance above the baseline reached by any part of any lowercase character. Contrast with maximum ascender and x height.
lowercase descent -
The maximum distance below the baseline reached by any part of any lowercase character. Contrast with maximum descender.
max baseline extent -
The maximum space occupied by the font (typically, the sum of the maximum ascender and maximum descender). Contrast with external leading and max char increment.
max char increment -
The maximum horizontal distance from the left edge of one character to the left edge of the next character to the right. Contrast with average char width and max baseline extent.
maximum ascender -
The maximum distance that any part of any character may extend above the x height of a font. Contrast with lowercase ascent and maximum descender.
maximum descender -
The maximum distance that any part of any character may extend below the x height of a font. Contrast with lowercase descent and maximum ascender.
maximum vert point size -
The maximum vertical dimensions to which a font can be resized. Contrast with minimum vert point size and nominal vert point size.
minimum vert point size -
The minimum vertical dimensions to which a font can be resized. Contrast with maximum vert point size and nominal vert point size.
nominal vert point size -
The normal display size of a font. Contrast with maximum vert point size and minimum vert point size.
pel -
The smallest element of a display surface that can be independently assigned color and density.
point -
Printer's unit of measurement. There are 72 points to an inch (approximately 3.5 points to a millimeter).
proportional spacing -
The space that each character occupies is in proportion to its width. See also font width. Contrast with fixed spacing.
Registry ID -
A code number that Presentation Manager uses to register a font file as a resource.
space default values -
Values that specify the space to be left between characters. Once defined, they are used for the entire font, and do not have to be specified for each character. However, they can be changed for characters that require more or less spacing than the defaults provide, by giving values for the a Space and the c Space. See also character increment.
strikeout position -
The distance of the strikeout character above the baseline (in pels). See also strikeout size and underscore position.
strikeout size -
The size of the strikeout character (in points). See also strikeout position and underscore size.
subscript position -
The distance of a subscript character of a font below the baseline (in pels). See also subscript size and superscript position.
subscript size -
The size of a subscript character (in points). See also subscript position and superscript size.
superscript position -
The distance of a superscript character above the baseline (in pels). See also subscript position and superscript size.
superscript size -
The size of a superscript character (in points). See also subscript size and superscript position.
target dev resolution X -
The number of pels per inch in the horizontal axis of a display device on which a font is to be displayed. Contrast with target dev resolution Y.
target dev resolution Y -
The number of pels per inch in the vertical axis of a display device on which a font is to be displayed. Contrast with target dev resolution X.
underscore position -
The distance in pels of the first underscore stroke from the baseline of a font. Successive strokes below this create a heavier underscore. See also strikeout position and underscore size.
underscore size -
The size of the underscore character measured in single strikeout strokes. See also strikeout size and underscore position.
x height -
The maximum distance above the baseline reached by a lowercase character. Contrast with em height and lowercase ascent.

---

[Back: Font Directory]
[Next: Graphics Attributes]