asyncio: mention that transports/protocols are low-level, streams are high-level
diff --git a/Doc/library/asyncio-stream.rst b/Doc/library/asyncio-stream.rst
index e457fe5..0772516 100644
--- a/Doc/library/asyncio-stream.rst
+++ b/Doc/library/asyncio-stream.rst
@@ -1,8 +1,8 @@
 .. currentmodule:: asyncio
 
-+++++++
-Streams
-+++++++
+++++++++++++++++++++++++
+Streams (high-level API)
+++++++++++++++++++++++++
 
 Stream functions
 ================