Why do the Hebrew Alphabetic Presentation Forms Exist

[Sławomir Osipiuk]

On Thu, Jun 4, 2020 at 4:42 AM abrahamgross--- via Unicode
<unicode at unicode.org> wrote:
>
> Whats TUS?
>

I believe that means "The Unicode Standard" and the section Richard
Wordingham was referring to is in Chapter 9:

Final (Contextual Variant) Letterforms. Variant forms of five Hebrew
letters are encoded
as separate characters in this block, as in Hebrew standards including
ISO/IEC 8859-8.
These variant forms are generally used in place of the nominal
letterforms at the end of
words. Certain words, however, are spelled with nominal rather than
final forms, particu-
larly names and foreign borrowings in Hebrew and some words in
Yiddish. Because final
form usage is a matter of spelling convention, software should not
automatically substitute
final forms for nominal forms at the end of words. The positional
variants should be coded
directly and rendered one-to-one via their own glyphs—that is, without
contextual analy-
sis.