(Required, except for Type 3 fonts) The maximum height above the baseline reached by glyphs in this font, excluding the height of glyphs for accented characters.

(Optional) The average width of glyphs in the font. Default value: 0.

(Required for fonts that have Latin characters, except for Type 3 fonts) The vertical coordinate of the top of flat capital letters, measured from the baseline.

(Optional; meaningful only in Type 1 fonts; PDF 1.1) A string listing the character names defined in a font subset. The names in this string must be in PDF syntax—that is, each name preceded by a slash (/). The names can appear in any order. The name .notdef should be omitted; it is assumed to exist in the font subset. If this entry is absent, the only indication of a font subset is the subset tag in the FontName entry.

(Required, except for Type 3 fonts) The maximum depth below the baseline reached by glyphs in this font. The value is a negative number.

(Required) A collection of flags defining various characteristics of the font.

(Required, except for Type 3 fonts) A rectangle (see Section 3.8.4, “Rectangles”), expressed in the glyph coordinate system, specifying the font bounding box. This is the smallest rectangle enclosing the shape that would result if all of the glyphs of the font were placed with their origins coincident and then filled.

(Optional; PDF 1.5; strongly recommended for Type 3 fonts in Tagged PDF documents) A string specifying the preferred font family name. For example, for the font Times Bold Italic, the FontFamily is Times.

(Optional) A stream containing a Type 1 font program.

(Optional; PDF 1.1) A stream containing a TrueType font program.

(Optional; PDF 1.2) A stream containing a font program whose format is specified by the Subtype entry in the stream dictionary.

(Required) The PostScript name of the font. This name should be the same as the value of BaseFont in the font or CIDFont dictionary that refers to this font descriptor.

(Optional; PDF 1.5; strongly recommended for Type 3 fonts in Tagged PDF documents) The font stretch value. It must be one of the following names (ordered from narrowest to widest): UltraCondensed, ExtraCondensed, Condensed, SemiCondensed, Normal, SemiExpanded, Expanded, ExtraExpanded or UltraExpanded. Note: The specific interpretation of these values varies from font to font. For example, Condensed in one font may appear most similar to Normal in another.

(Optional; PDF 1.5; strongly recommended for Type 3 fonts in Tagged PDF documents) The weight (thickness) component of the fully-qualified font name or font specifier. The possible values are 100, 200, 300, 400, 500, 600, 700, 800, or 900, where each number indicates a weight that is at least as dark as its predecessor. A value of 400 indicates a normal weight; 700 indicates bold. Note: The specific interpretation of these values varies from font to font. For example, 300 in one font may appear most similar to 500 in another.

(Required) The angle, expressed in degrees counterclockwise from the vertical, of the dominant vertical strokes of the font. (For example, the 9-o’clock position is 90 degrees, and the 3-o’clock position is –90 degrees.) The value is negative for fonts that slope to the right, as almost all italic fonts do.

(Optional) The spacing between baselines of consecutive lines of text. Default value: 0.

(Optional) The maximum width of glyphs in the font. Default value: 0.

(Optional) The width to use for character codes whose widths are not specified in a font dictionary’s Widths array. This has a predictable effect only if all such codes map to glyphs whose actual widths are the same as the value of the MissingWidth entry. Default value: 0.

(Optional) The thickness, measured vertically, of the dominant horizontal stems of glyphs in the font. Default value: 0.

(Required, except for Type 3 fonts) The thickness, measured horizontally, of the dominant vertical stems of glyphs in the font.

(Required) The type of PDF object that this dictionary describes; must be FontDescriptor for a font descriptor.

(Optional) The font’s x height: the vertical coordinate of the top of flat nonascending lowercase letters (like the letter x), measured from the baseline, in fonts that have Latin characters. Default value: 0.