Presentational HTML focuses on style and appearance of content. It is deprecated.

Font element is one of them. While it works, styling should always be set in CSS

Semantic HTML is the recommended practice. It describes the content of elements. It's much easier to understand and read

header, section, nav and figure are some of the examples of semantic elements

Semantic describes the content, while presentational focuses on appearance

This is some emphatic text

This is emphasized another way

If you use italics like this, it should be when they have a semantic meaning, else use css

b is used to bring attention. It usually displays text in boldface