+ 2.0 3.0 3.2 4.0 1.0 2.0 3.0 4.0   1.0 2.0 3.0 4.0   1.0 2.0       1.0 2.1       0.9 1.2

<fn> container start tag required end tag required Sandia Reference

This tag has not been included in the HTML 4.0 specification.

The FN element logically identifies text to be presented as a footnote. The reference location for the footnote is expected to be an A element whose HREF attribute references the ID of the FN element.

Translation: this was an attempt to create footnotes in HTML. The syntax was proposed as follows:

The footnote would be located in the document by an anchor
<a href="#footnote1" id="fnaardvark">^¹</a>
which references a
<fn id="footnote1"><a href="#fnaardvark">^¹
later in the document.
</fn>
The idea is - that when you click on the footnote link, a small window pops up and displays the content of the footnote. Neat if it would work.

class= + 2.0 3.0 3.2 4.0
dir=
	"ltr"
	"rtl"
href= 0.9 1.2		This is the link to the footnote text. The target is established by using the 'id="'" attribute below. Not many browsers support this yet. It has potential. It must be noted that they specify that this attribute is generally considered obsolete.
id= + 2.0 3.0 3.2 4.0 0.9 1.2		WebTV is the first to use this implementation. It must be noted that they specify that this attribute is generally considered obsolete.
lang= + 2.0 3.0 3.2 4.0