Using Semantic Markup
Rather than thinking of specific HTML tags as tools to make text “look” a certain way, think of tags as tools that describe the purpose of the text, and cascading style sheets as the tool to make the text within those appropriate tags appear the way you want it to.
For instance, lists, by nature, group similar elements together in a way that consecutive paragraphs don’t. More specifically with lists, the definition list, ordered list, and unordered list mean different things based on their explicit intended use. An <h1> element gives text a more explicit meaning than the same words marked up with a large font size. Similarly, an <em> (emphasized) or a <strong> tag adds additional semantic meaning to a word, whereas a <b>