XHTML could either be served as HTML or as XML. When served as XML it would not render in all browsers, but when served as HTML it would. Since serving as XML d

XHTML could either be served as HTML or as XML. When served as XML it would not render in all browsers, but when served as HTML it would. Since serving as XML did not provide any particular value for the document author, there was no reason to use it. But XHTML served as HTML is just HTML with some extra slashes which are ignored.