Phones and allophones.
there are many
different versions of that sound-type regularly
produced in actual speech (“in the
mouth”). We can describe those different versions as
phones.
Phones.
Are phonetic units and appear in square brackets.
When we have a set of phones, all of which are
versions of one phoneme, we add the prefix “allo-” (=
one of a closely related set) and
refer to them as allophones.