Visual Organization + Communication Design
The distance from the baseline of one line of type to another is called line spacing.It is also called leading, in reference to the strips of lead used to separate lines of metal type. The default setting in most layout and imaging software is 120 percent of the type size. Thus 10-pt type is set with 12 pts of line spacing. Designers play with line spacing in order to create distinctive typographic arrangements. Reducing the standard distance creates a denser typographic color, while risking collisions between ascenders and descenders. Expanding the line spacing creates a lighter, more open text block. As leading increases, lines of type become independent graphic elements rather than parts of an overall visual shape and texture.
– Ellen Lupton, from Thinking With Type
Below is an example of the impact of variable line spacing aka leading, on the same paragraph of text.
Lets look at some examples of typographic texture.