From 34f374dafc3f957190c74228dfdc949711287436 Mon Sep 17 00:00:00 2001
From: Oleksii Masnyi <aleksey.masny@gmail.com>
Date: Fri, 15 Nov 2019 19:30:46 +0200
Subject: [PATCH] Update README.md

---
 README.md | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/README.md b/README.md
index bf2116b..6db19e3 100644
--- a/README.md
+++ b/README.md
@@ -36,7 +36,7 @@ Paper.init(context);
 * All other APIs (`write`, `read` etc.) are thread-safe and obviously must be called outside of UI thread. Reading/writing for different `key`s can be done in parallel. 
  
 ### Save
-Save any object, Map, List, HashMap etc. including all internal objects. Use your existing data classes as is.
+Save any object, Map, List, HashMap etc. including all internal objects. Use your existing data classes as is. Note that key is used as file name to store the data and so *cannot* contain symbols like `/`.
 
 ```java
 List<Person> contacts = ...