Which CSS property makes text italic?

The CSS property that makes text italic is `font-style`.

Setting `font-style: italic;` asks the browser to use an italic face of the selected font. If that font has no true italic design, the browser may use an oblique version or synthesize a slant. CSS also supports `normal` and `oblique`, while newer font systems can expose more precise variations through related font properties.

Italic type has a long history in typography. It emerged in Renaissance Italy, with influential early designs associated with Aldus Manutius and Ludovico Arrighi. Modern italic fonts are not always just mechanically slanted versions of roman letters: true italics may use different letterforms inspired by handwriting, whereas oblique faces usually keep the same forms and tilt them.

`font-style` is easy to confuse with HTML's `<i>` and `<em>` elements. `<i>` traditionally signals an alternate voice or convention, while `<em>` expresses emphasis; their default appearance is often italic, but their semantic meaning matters. Use CSS when the goal is purely visual styling. `text-decoration` controls lines such as underlining, `font-weight` controls boldness, and `font-variant` controls alternate typographic forms.