--- a/nashorn/docs/JavaScriptingProgrammersGuide.html	Mon Jun 24 19:06:01 2013 +0530
+++ b/nashorn/docs/JavaScriptingProgrammersGuide.html	Tue Jun 25 17:31:19 2013 +0530
@@ -227,6 +227,16 @@
 it. Note that the syntax to access Java objects, methods and fields
 is dependent on the scripting language. JavaScript supports the
 most "natural" Java-like syntax.</p>
+<p>
+Nashorn script engine pre-defines two global variables named "context"
+and "engine". The "context" variable is of type javax.script.ScriptContext
+and refers to the current ScriptContext instance passed to script engine's
+eval method. The "engine" variable is of type javax.script.ScriptEngine and
+refers to the current nashorn script engine instance evaluating the script.
+Both of these variables are non-writable, non-enumerable and non-configurable
+- which implies script code can not write overwrite the value, for..loop iteration
+on global object will not iterate these variables and these variables can not be
+deleted by script.
 <pre><code>
 // <a href="source/ScriptVars.java">ScriptVars.java</a>