--- a/README.rst	Sat Sep 20 23:58:41 2014 +0300
+++ b/README.rst	Sun Sep 21 01:07:55 2014 +0300
@@ -13,7 +13,16 @@
 Game rules.
 ===========
 
-TODO
+4x4 board tiles filled by nambers or empty.
+
+During each move one of free tiles was filled by value 1 or 2 (2 with probability 10%).
+
+You can move tiles in one of four possible direction: left/right/up/dowm.
+
+Each move every tiles fill empty space in selected direction. If two tiles have same numbers ``N``
+them was merged into tile with number ``N+1``. Merges performed from head of direction.
+
+Your goal is to reach tile with number ``11`` or better.
 
 AI discussion.
 ==============