Bold typeface

In typography, emphasis is the strengthening of words in a text with a font in a different style from the rest of the text, to highlight them. It is the equivalent of prosodic stress in speech.

The most common methods in Western typography fall under the general technique of emphasis through a change or modification of font: italics, boldface and small caps. Other methods include the alteration of LETTER CASE and spacing as well as color and *additional graphic marks*.

The human eye is very receptive to differences in "brightness within a text body". Therefore, one can differentiate between types of emphasis according to whether the emphasis changes the “blackness” of text, sometimes referred to as typographic color. A means of emphasis that does not have much effect on blackness is the use of italics, where text is written in a script style, or oblique, where the vertical orientation of each letter of the text is slanted to the left or right. With one or the other of these techniques (usually only one is available for any typeface), words can be highlighted without making them stand out much from the rest of the text (inconspicuous stressing). This is used for marking passages that have a different context, such as book titles, words from foreign languages, and the like.

By contrast, a bold font weight makes letters of a text thicker than the surrounding text. Bold strongly stands out from regular text, and is often used to highlight keywords important to the text's content and allowing such words to be visually scanned with ease. For example, printed dictionaries often use boldface for their keywords, and the names of entries can conventionally be marked in bold. If a publisher prefers not to use bold, or has already used it for another purpose, a second form of emphasis can be introduced by using a lightface or thin version of the main text font, although this is not very common.

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