diff --git a/src/btree_demo.cpp b/src/btree_demo.cpp
index e26a8b21..4f745193 100644
--- a/src/btree_demo.cpp
+++ b/src/btree_demo.cpp
@@ -1,3 +1,4 @@
+//Demo for binary tree
 #include <stdio.h>
 #include "btree.h"