diff --git a/append only.md b/append only.md
index 120ae24a7..b25b2d3fc 100644
--- a/append only.md	
+++ b/append only.md	
@@ -2,4 +2,6 @@
 
 - a [[property]]
   - [[wp]] https://en.wikipedia.org/wiki/Append-only
+  - existing data is [[immutable]], but you can append new data to it
+  - goes well with [[functional programming]]