diff --git a/README.md b/README.md
index 11c2f7e..7a605aa 100644
--- a/README.md
+++ b/README.md
@@ -13,29 +13,6 @@ ALLCING is a structured logging library featuring on lightweightness.
 - compact log data with simple binary format
 - completely-free license (WTFPLv2)
 
-# Log Data Format
-
-```
-# [TOKEN] means TOKEN is optional
-# <TOKEN> means TOKEN is constant and refer allcing.h for actual value
-
-ROOT := CHUNK_BEGIN | CHUNK_END | CHUNK_CHECK
-
-CHUNK_BEGIN := <ACG_CHUNK_BEGIN> [CHUNK_DATA]
-CHUNK_END   := <ACG_CHUNK_END>   [CHUNK_DATA]
-CHUNK_CHECK := <ACG_CHUNK_CHECK> [CHUNK_DATA]
-
-CHUNK_DATA := CHUNK_PAD | CHUNK_BLOB | CHUNK_CTX | CHUNK_LOC | CHUNK_DATA
-CHUNK_PAD  := <ACG_CHUNK_PAD>  PAD
-CHUNK_BLOB := <ACG_CHUNK_BLOB> BLOB
-CHUNK_CTX  := <ACG_CHUNK_CTX>  UINT(64) UINT(16)
-CHUNK_LOC  := <ACG_CHUNK_LOC>  BLOB
-
-PAD     :=
-BLOB    :=
-UINT(x) :=
-```
-
 # License
 
 Do What The Fuck You Want to Public License v2