The <b> element makes the text bold without adding any particular importance. Typical use cases include keywords in a summary or product names in a review — whenever you need to make certain words noticeable.

At the dawn of web design, the <b> tag was the only way to make text bold. Nowadays, when bold text is a style choice, the best practice is to use the CSS property font-weight. As a rule of thumb, if you need to make a block of text bold, you will most likely need CSS; if it's about making a keyword look prominent, the <b> tag is the right choice.^[1]