Presentational vs Semantic Elements
Most HTML elements used within
body element can be categorized as presentational elements and/or semantic elements.
A presentational element is an element that does not convey to computer programs reading it what its content is from the semantic perspective but only control how the content is displayed visually.
A semantic element is an element that conveys to computer programs, such as search engine web crawlers or assistive screen readers, what its content is from the semantic perspective. In addition, web browsers may also display visually a semantic element in a certain way. Furthermore, semantic elements are a way of describing their meaning in code to facilitate and enhance the quality of development.
As noted, presentational elements only control how an HTML document is displayed visually but do not describe semantically what their contents are.
Since 1997 using presentational elements has been discouraged in favor of using Cascading Style Sheets. Further, some presentational elements have their semantic "counterparts" which not only display visually their contents in a way similar to the presentational components but also tell computer programs what their content is. Such presentational elements and their "counterparts" are:
bigelement for making the content's font larger - use semantic
h1for headings or
font-sizeproperty for non-headings,
uelement for underlining the content's font - use semantic
eminstead for emphasis,
bfor marking up keywords, and
markfor highlighting references,
strikeelements for striking out the content's font - use semantic