Ligature

A ligature is a single glyph formed by combining two or more characters. Common ligatures include fi, fl, ff, ffi, and ffl, where the hook of the 'f' would collide with the dot of the 'i' or the ascender of the 'l'. Ligatures solve these collision problems while adding typographic refinement. In CSS, ligatures are controlled through font-variant-ligatures or the shorthand font-feature-settings. Most modern browsers enable common ligatures by default. Programming fonts like Fira Code use ligatures extensively to render operators like => as arrows and != as the not-equal symbol.