A typeface (or font family) is a design of letters, numbers and other symbols, to be used in printing or for electronic display. Most typefaces include variations in size (e.g., 24 point), weight (e.g., light, bold), slope (e.g., italic), width (e.g., condensed), and so on. Each of these variations of the typeface is a font.

There are thousands of different typefaces in existence, with new ones being developed constantly.

The art and craft of designing typefaces is called type design. Designers of typefaces are called type designers and are often employed by type foundries. In desktop publishing, type designers are sometimes also called "font developers" or "font designers" (a typographer is someone who uses typefaces to design a page layout).

Every typeface is a collection of glyphs, each of which represents an individual letter, number, punctuation mark, or other symbol. The same glyph may be used for characters from different writing systems, e.g. Roman uppercase A looks the same as Cyrillic uppercase А and Greek uppercase alpha (Α). There are typefaces tailored for special applications, such as cartography, astrology or mathematics.

In professional typography, the term typeface is not interchangeable with the word font, because the term font has historically been defined as a given alphabet and its associated characters in a single size. For example, 8-point Caslon Italic was one font, and 10-point Caslon Italic was another. Historically, a font came from a type foundry as a set of "sorts", with number of copies of each character included.

As the range of typeface designs increased and requirements of publishers broadened over the centuries, fonts of specific weight (blackness or lightness) and stylistic variants (most commonly regular or roman as distinct from italic, as well as condensed) have led to font families, collections of closely related typeface designs that can include hundreds of styles. A typeface family is typically a group of related typefaces which vary only in weight, orientation, width, etc., but not design. For example, Times is a typeface family, whereas Times Roman, Times Italic and Times Bold are individual typefaces making up the Times family. Typeface families typically include several typefaces, though some, such as Helvetica, may consist of dozens of fonts. In traditional typography, a font family is a set of fonts within the same typeface: for example Times Roman 8, Times Roman 10, Times Roman 12 etc. In web typography, the term 'font family' (as specified using the HTML code span style="font-family: ) may equate to a 'typeface family' or even to a very broad category such as sans-serif that encompass many typeface families.

Another way to look at the distinction between a computer font and a typeface is that a computer font is the vessel (e.g. the software) that provides a set of characters with a given appearance, whereas a typeface is the actual design of such characters. Therefore, a given typeface, such as Times, may be rendered by different fonts, such as computer font files created by this or that vendor, a set of metal type characters etc. In the metal type era, a font also meant a specific point size, but with digital scalable outline fonts this distinction is no longer valid, as a single font may be scaled to any size.

The first "extended" font families, which included a wide range of widths and weights in the same general style emerged in the early 1900s, starting with ATF's Cheltenham (1902–1913), with an initial design by Bertram Grosvenor Goodhue, and many additional faces designed by Morris Fuller Benton. Later examples include Futura, Lucida, ITC Officina. Some became superfamilies as a result of revival, such as Linotype Syntax, Linotype Univers; while others have alternate styling designed as compatible replacements of each other, such as Compatil, Generis.