diff --git a/README.md b/README.md
index 2627a47..dbe0cc9 100644
--- a/README.md
+++ b/README.md
@@ -180,7 +180,7 @@ When you want to see whats happening do a debug run;
 
 Since `.RECIPEPREFIX` is added to make, it broke library support and having per call different  
 dynamic white space rules is also really hard for a human brain.  
-To fix make5 will use binary files to express the rules.
+To fix make5 will use (IBM spec) binary files to express the rules.
 
 * Add a few new define's to have official make documentation
 * BUG: Unicode read+parse ok but function call fails on `include $(MB__BASEPATH)/lib/make/प्रणालीᐥᔆʸᔆᐪᓫᔿ/mb_doc.mk`.