How to create a helpfile

Helpfiles are basically html. Lots of things are not supported that you'd expect, but a helpfile you create in this format will be perfectly viewable from a web browser.

This could, of course, be texinfo'ed, but that is not particularly well documented (except by texinfo documents. Ick) and it looks like it's a very expensive (spacewise) operation.

HTML
This, and /HTML, delimit a helpfile.
TITLE
Is the title of a help document.
A nested table
bullet me now
On the lone prairie
And if this works
I'll be very surprised

Helpfile navigation: [tab] goes to next @link or @index

Special characters:
<	less than.
>	greater than.
&	ampersand.
!	decimal 33.
junk