One reason it
might be good to have a section about that is that there is a lot of confusion and wrong information about
which characters that the shell treats specially in some contexts require quoting at all, and in what contexts. For example,
this answer says that
!
is expanded in
"
"
because
!
is a reserved word. But that's totally unrelated to the reason it is expanded, and other reserved words are
not treated specially in double quotes.