diff --git a/runtime/doc/if_ruby.txt b/runtime/doc/if_ruby.txt
index 1b4fd40..572a6ec 100644
--- a/runtime/doc/if_ruby.txt
+++ b/runtime/doc/if_ruby.txt
@@ -145,7 +145,7 @@
 
 Methods:
 
-name		Returns the name of the buffer.
+name		Returns the full name of the buffer.
 number		Returns the number of the buffer.
 count		Returns the number of lines.
 length		Returns the number of lines.
@@ -181,6 +181,7 @@
 width		Returns the width of the window.
 width = {n}	Sets the window width to {n}.
 cursor		Returns a [row, col] array for the cursor position.
+		First line number is 1 and first column number is 0.
 cursor = [{row}, {col}]
 		Sets the cursor position to {row} and {col}.