The <i> tag makes the text inside it look italic. In the early days of HTML, it was the only way to make the text look italic. Nowadays, we use this tag for words and phrases that differ from the regular text for some reason — titles, terms, idioms, words in other languages, characters' thoughts in stories, etc. For example, in the Matrix franchise, a glitch is a mistake in the system that results in deja vu.

Similarly to the <b> tag, the <i> tag is not for styling text. Use the CSS font-style property instead if needed for style purposes.