diff --git a/amaranth/lib/data.py b/amaranth/lib/data.py
index f522d74..302aaf1 100644
--- a/amaranth/lib/data.py
+++ b/amaranth/lib/data.py
@@ -481,6 +481,11 @@ class ArrayLayout(Layout):
 
         Arrays that have padding can be described with a :class:`FlexibleLayout`.
 
+    .. note::
+
+        This class, :class:`amaranth.lib.data.ArrayLayout`, is distinct from and serves a different
+        function than :class:`amaranth.hdl.Array`.
+
     Attributes
     ----------
     elem_shape : :class:`.ShapeLike`
diff --git a/docs/guide.rst b/docs/guide.rst
index 0474f48..4946d73 100644
--- a/docs/guide.rst
+++ b/docs/guide.rst
@@ -813,6 +813,10 @@ Crucially, this means that any Python object can be added to an array; the only
 
     Each time an array proxy object with :py:`n` elements is used in an expression, it generates a multiplexer with :py:`n` branches. However, using :py:`k` of such array proxy objects in an expression generates a multiplexer with :py:`n**k` branches. This can generate extremely large circuits that may quickly exhaust the resources of the synthesis target or even the available RAM.
 
+.. note::
+
+    Arrays, :class:`amaranth.hdl.Array`, are distinct from and serve a different function than :class:`amaranth.lib.data.ArrayLayout`.
+
 
 .. _lang-data: