Use the SUB element to create sub-scripted text. Sub-scripted text
appears about half the height of the original text and aligns at the
bottom or just below the baseline of the original font.
This element requires a closing tag.
||Identifies this tag to reference in script (program code)
||Define the class used to render this element (defined by a style sheet)
||A title that is associated with the element (displayed as a tooltip in Internet Explorer)
||Defines an inline style which may contain any CSS style properties you want
to apply to the contents of the SUB element.