Boldface

Boldface refers to a typographic style in which characters are darker and thicker than the surrounding text. It is used to draw attention to a word or phrase and to indicate section headings. In most typefaces, bold is a distinct weight within a font family, produced by increasing the stroke thickness of the letters. Bold characters can be found in many scripts, not only Latin.

Historically, the concept of bold type emerged with early printed books as printers sought ways to emphasize text. In metal type, separate bold weights were cast as companions to regular faces. In the digital era, bold is typically a font weight such as bold or semibold, and can also be generated synthetically when a typeface does not include a true bold face. In digital typography, font-weight values like 700 are commonly used.

Bold is commonly used for emphasis and for headings or subheadings. Proper typographic practice reserves bold for key terms and structure rather than for every emphasized word; overuse can reduce readability. In web content, bold styling alone provides visual emphasis, while semantic HTML such as strong or b elements conveys emphasis to assistive technologies.

Accessibility and readability considerations include maintaining high contrast, using bold at appropriate sizes, and avoiding bold in long passages. Some scripts and styles offer true bold variants, while others rely on faux bold rendering. When possible, pair bold with complementary typography such as a clear sans-serif body text for headings, and ensure that bold text remains legible at intended viewing sizes.