What is the difference between a font and a typeface?

In many picture books, the copyright page includes information about the typeface used for the text. For example, "Type set in 18-point Gill Sans Extra Bold."

Many people use "font" and "typeface" interchangeably, but there is a difference. A typeface is the name, such as Gills Sans, whereas font refers to the variety of sizes and weights of the typeface. Designers choose typefaces but use fonts to set the text in a picture book. As desktop publishing became more popular, the two become synonymous.

A good way to remember the difference font is to typeface as chapters are to a book. Chapters make a book; fonts make a typeface. The example are different weights of the Gill Sans typeface.

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