diff --git a/Doc/tutorial/datastructures.rst b/Doc/tutorial/datastructures.rst
index 62be9a0..b95aca8 100644
--- a/Doc/tutorial/datastructures.rst
+++ b/Doc/tutorial/datastructures.rst
@@ -466,7 +466,7 @@
    {'a', 'r', 'b', 'c', 'd'}
    >>> a - b                              # letters in a but not in b
    {'r', 'd', 'b'}
-   >>> a | b                              # letters in either a or b
+   >>> a | b                              # letters in a or b or both
    {'a', 'c', 'r', 'd', 'b', 'm', 'z', 'l'}
    >>> a & b                              # letters in both a and b
    {'a', 'c'}