HTML and CSS Reference
Sectioning content is used to divide an HTML document into sections. Every section of the
document would generally have its own header, main content and possibly footer.
In HTML revisions prior to HTML5, more notably HTML 4 and XHTML 1, the choices for
sectioning content were rather limited. The only sectioning elements designers had to work
with were the <body> and <div> tags; <div> is a generic element used to signify a division.
This made the semantic markup of a document virtually impossible and made it difficult for
screen readers and other assistive devices to evaluate a page. The new HTML5 semantic
markup makes it easy for machines and people alike to understand the content's meaning
and context and provides a way to differentiate the key content from sidebars or unrelated
Each semantic element of HTML5 has no specific output, color, or design.. Unless it has
been styled with CSS, each semantic element will be invisible, and its contents will appear
drab and monotone when viewed in a web browser.
Note: Theoretically, sectioning elements allow us to create document outlines using
headings, form titles, table titles, and any other appropriate landmarks that map out
the document. The outlining algorithm has been clearly defined in the HTML5 spec,
but browsers and assistive technologies have not yet implemented it.