span and div

In HTML and XHTML, span and div tags are used to describe content that cannot be properly described by other, more semantic tags. The div tag defines a division or section within an HTML or XHTML document, hence its name, div.Proper semantic markup requires that all elements describe the type of data contained within. For example, in HTML and XHTML, a p (paragraph) element should contain a paragraph of text, and an h1 element should contain the highest-level header of the page. In HTML and XHTML, span and div are the only elements that carry no innate semantic meaning, besides the logical grouping of the enclosed elements.
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