Glossary » typography
the design of letterforms, and the selective use of appropriate type (in appropriate fonts) for the display of text. Typographers often specialize in the design of fonts and of logos, but typography plays a role in any context in which text is displayed. Type is often selected for its style, mood, rhythm, and legibility. Typography also encompasses the layout of text: size, orientation, alignment, spacing (leading and kerning), and margins.
Typography plays an important role in usability by affecting the legibility of the text (and thus the speed and comfort of reading), by providing appropriate emphasis, and by establishing the flow of eye movement through written material.