Bold icon

When to use it

The heavy 'B' is the universal rich-text bold control — it belongs in a formatting toolbar beside italic and underline. Most sets draw a literal serif or slab B; Phosphor names it text-b. The glyph only makes sense in an editing context, so don't borrow it to mean 'emphasis' generally; in a toolbar it's unmistakable, out of one it's just a letter.

Reach for bold only inside a text-formatting toolbar, where a row of B / I / U primes the user to read letterforms as controls. It toggles heavier weight on the selection and should show an active state when the caret sits in bold text. Outside an editor the lone B reads as a letter, not a command, so keep it with its formatting siblings rather than using it as a standalone emphasis marker.

• Reaching for Italic? Reach for the slanted I for slant emphasis; the two sit side by side but toggle different styles.
• Reaching for Edit? Reach for the pencil to enter or open editing, not to apply a specific type style.