Terminology

Terminology

Before discussing how to use fonts, consider these terms.

Typography

Typography is the art and technique of working with type. In traditional typography, the term type refers to a piece of wood or metal with a raised image of a character or characters on its upper face. Such pieces of wood or metal are assembled into lines and pages, which are printed by a letterpress process. What typographers do with type is called typesetting or composition. Type can also refer to the images produced by using such pieces of wood or metal.

Traditional typesetting is seldom used today. In modern typography, type usually refers to the images produced on typesetting or composition systems, which do not use wooden or metal type, such as photo and digital composition systems. The typography on a digital system, such as a digital computer, is called digital typography.

Digital typography is based on a hierarchy of objects called characters, fonts, and font families (or typefaces). Numeric values or measurements related to those objects can be divided into character metrics, font metrics, and typeface metrics. Sometimes all information about a font family, or typeface, is stored in a set of font files, but sometimes metric information for a set of font files is stored in a separate file called the font metric file.

Character

A character is a graphical or mathematical representation of a glyph. Letters, digits, punctuation marks, mathematical symbols, and cursors are examples of glyphs.

Font

A font is a set of characters, that is, a set of representations of characters. In a bitmap font, the shape of each character is represented by a rectangular array of bit values, 1 or 0, forming a bitmap of the shape. In an outline font, the shape of a character is represented by a mathematical description of its outline.

A distinction exists between a base and composite font. A base font is a set of characters of the same size and style. Characters in a base font usually match one another in size, style, weight, and slant because their shape, size, position, and spacing have been carefully designed by a skilled font designer. A composite font is composed of base fonts with various attributes, for example roman and italic, or book weight and semibold.

Font Family, or Typeface

A professional font designer usually creates an entire font family, or typeface, composed of a variety of base fonts with related forms, rather than a single font. A base font family, or typeface, is a set of base fonts with the same style or design. A composite font family, or composite typeface, is composed of base font families. A base font family can consist of bitmap fonts in certain sizes, a scalable font that can be used to produce bitmap fonts in different sizes, or both.