A font is a coordinated set of letters, numerals, punctuation marks, and symbols sharing a specific design, weight, style, and size. In older metal type, a font referred to the physical assortment of sorts; in digital publishing, it usually refers to a software file or family member. The font chosen for a poetry book affects legibility, line length, page color, and tone. A quiet serif face may suit dense lyric work, while a stark sans serif may support experimental visual poems.

A "font" historically refers to a complete assortment of metal type characters in a single specific size and style (e.g., 10-point Caslon Italic), whereas a "typeface" refers to the overarching visual design family (e.g., Caslon). In modern digital publishing, the terms are often used interchangeably, but understanding the distinction is invaluable for book historians and textual critics. For poets, the choice of font impacts how a poem is experienced: a delicate serif font like Bembo conveys classical elegance, while a heavy slab-serif or typewriter font imparts a gritty, immediate texture. Related terms include typeface, point size, weight, and font family.