#14155: add a note about \b.
diff --git a/Doc/library/re.rst b/Doc/library/re.rst
index 02251cf..b82b397 100644
--- a/Doc/library/re.rst
+++ b/Doc/library/re.rst
@@ -398,6 +398,9 @@
\r \t \v \x
\\
+(Note that ``\b`` is used to represent word boundaries, and means "backspace"
+only inside character classes.)
+
Octal escapes are included in a limited form: If the first digit is a 0, or if
there are three octal digits, it is considered an octal escape. Otherwise, it is
a group reference. As for string literals, octal escapes are always at most