Minor.

navig.html

@@ -163,7 +163,7 @@ $(function() {
     <ul>
         <li><pre style = "display:inline">X.type === "fun" && (X.v1, true)</pre> (we are at the beginning of a function and v1 is defined in the local interpreter context),</li>
         <li><pre style = "display:inline">X.line === 32 && X.t.tag === "trm_set" && X.t.field === "bar"</pre> (we are at line 32 and we are setting the field “bar” of the current location),</li>
-        <li><pre style = "display:inline">x.foo === 12</pre> (the program variable has field “foo” equals to 12),</li>
+        <li><pre style = "display:inline">y.foo === 12</pre> (the program variable “y” points to an object whose field “foo” is equal to 12),</li>
         <li><pre style = "display:inline">X.heap[0].bar === 12</pre> (the first cell of the heap has a field “bar” defined equal to 12).</li>
     </ul></div>