#4983: clarify what "byte sequence" is.

Doc/library/stdtypes.rst

@@ -594,16 +594,17 @@ generator object) supplying the :meth:`__iter__` and :meth:`__next__` methods.
 Sequence Types --- :class:`str`, :class:`bytes`, :class:`bytearray`, :class:`list`, :class:`tuple`, :class:`range`
 ==================================================================================================================
 
-There are six sequence types: strings, byte sequences, byte arrays, lists,
-tuples, and range objects.  (For other containers see the built-in
-:class:`dict`, :class:`list`, :class:`set`, and :class:`tuple` classes, and the
-:mod:`collections` module.)
+There are six sequence types: strings, byte sequences (:class:`bytes` objects),
+byte arrays (:class:`bytearray` objects), lists, tuples, and range objects.
+
+For other containers see the built-in :class:`dict`, :class:`list`,
+:class:`set`, and :class:`tuple` classes, and the :mod:`collections` module.
 
 .. index::
    object: sequence
    object: string
    object: bytes
-   object: buffer
+   object: bytearray
    object: tuple
    object: list
    object: range