Typeface
A typeface is a set of glyphs — letters, numbers, punctuation, and other characters — of the same design. A single typeface may include many variations in size, weight, width, and slope (or italics). Each of these variations of a typeface is known as a font.
Most operating systems have several dozen typefaces pre-installed, giving users plenty of design choices. Word processors and graphic design programs allow the user to use any installed font for text. Changing the typeface alters the look and feel of a block of text, giving it a classic, contemporary, or playful appearance. Some typefaces work better for longer pieces of text, while others are more suited to shorter blocks like titles, headlines, and captions.
There are countless typefaces available that a user can install on their computer, which can be managed from a Settings category or Font Book application. Most typefaces are a set of several files, one for each of its fonts. For example, a version of Times New Roman may have one font file each for regular text, italics, bold, and bold italics; a professional version of Helvetica for graphic designers may also have a series of font files for different weights of the typeface, from ultra-thin to extra-bold.
Styles of Typefaces
Most typefaces are classified into one of several styles based on some important design elements. The five common styles are serif, sans serif, script, monospaced, and display, with serif and sans serif being the most often used.
Serif typefaces include serifs on the letter forms. A serif is a small line or detail at the end of a larger stroke, like the feet at the bottom of the letter M. They are often used for body text since the serifs help guide the eye from one letter to the next and are often more legible in small sizes. Times New Roman, Palatino, and Baskerville are three common serif typefaces.
Sans-serif typefaces lack serifs. The letter forms are a little more geographic, with less flair than those with serifs. While generally reserved for shorter blocks of text like titles, headlines, and captions, some sans serif typefaces are designed for legibility in body text nearly as well as serif typefaces. Helvetica, Arial, and Verdana are some common sans-serif typefaces.
The other classes of typefaces are still frequently used, but not for body text. Script typefaces mimic handwriting or calligraphy. Monospaced typefaces space every glyph equally; since letters will line up neatly in columns, monospaced typefaces are used by developers when writing source code. Display fonts are ideal for headlines and titles, often with design elements that make them difficult to read at small sizes.