An XHTML element indicates structure in an XHTML document and a way of hierarchically arranging content. XHTML elements have both properties attributes and content, according to the appropriate XHTML DTD as specfied (allowable and required). A variety of structures are represented by elements like headings, hypertext links, paragraphs, lists, embedded media.

Many of XHTML elements hold attributes in the start tags, defining desired behavior or indicating additional element properties. Unlike HTML here there is always a need of end tag. There are some elements which are not subset of any official DTDs, but still are supported by some browsers and are also used in some web pages. All such elements may be ignored or displayed improperly on browsers which do not support them.

Sometimes XHTML elements are referred to as "tags". though many prefer "tag" strictly to the semantic structures to delimit the start and end of an element.

WE should start using lowercase tags if we have to prepare ourself for the next generations of HTML, XHTML which is next generation HTML demands for lowercase tags