These document-wide attributes provide control over the form of generated HTML—you use them only for writing HTML
excluded allows control over the tags used. The recognized values in the
excluded array are (case-insensitive) HTML tags, plus DOCTYPE (representing a doctype declaration) and XML (representing an XML declaration). By default, if this attribute is not present, the excluded elements will be those deprecated in HTML 4 (APPLET, BASEFONT, CENTER, DIR, FONT, ISINDEX, MENU, S, STRIKE, and U) plus XML. If XML is on the list, HTML forms are used; if XML is not on the list, XHTML forms are used where there is a distinction. Either
text may be used to control the encoding used for generated HTML; character entities are used for characters not representable in the specified encoding.
prefix allows some control over formatting.