It is a typographic style used to emphasize words or phrases, often for the following reasons:
* Emphasis: To highlight a word or phrase and draw attention to its importance.
* Titles of works: Titles of books, movies, songs, articles, etc. are usually italicized.
* Foreign words: Words from other languages that are not commonly used in English are often italicized.
* Scientific names: The scientific names of species are often italicized (e.g., *Homo sapiens*).
* Legal terms: Legal terms and phrases may be italicized for clarity.
* Technical terms: Specialized terms or concepts might be italicized for emphasis and distinction.
Note: In some cases, underlining can be used instead of italics, though this is less common today.