diff --git a/Doc/library/site.rst b/Doc/library/site.rst
index d93e4dc7c75f1a..03d6278ac86dd8 100644
--- a/Doc/library/site.rst
+++ b/Doc/library/site.rst
@@ -78,6 +78,12 @@ directory rather than a file.  No item is added to ``sys.path`` more than
 once.  Blank lines and lines beginning with ``#`` are skipped.  Lines starting
 with ``import`` (followed by space or tab) are executed.
 
+.. note::
+
+   On Windows, a file whose name has the form :file:`._pth` is handled
+   differently; it is used exclusively by the Windows-only "embeddable
+   distribution" to provide a self-contained Python environment.
+
 .. note::
 
    An executable line in a :file:`.pth` file is run at every Python startup,
@@ -308,4 +314,3 @@ value greater than 2 if there is an error.
 
    * :pep:`370` -- Per user site-packages directory
    * :ref:`sys-path-init` -- The initialization of :data:`sys.path`.
-