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 a typeface but use fonts to set the text in a picture book.

A good way to remember the difference is to think of it this way: font is to typeface as chapter to a book. A typeface is made up of fonts and a book is made up of chapters. To the right are fonts with different weights from the Gills Sans typeface, such as light, medium, and bold.

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