diff --git a/tconfpy.3 b/tconfpy.3
index 9c49659..bbd9512 100644
--- a/tconfpy.3
+++ b/tconfpy.3
@@ -1312,7 +1312,118 @@
 fi
    
 
-.SS Pre-Defined Variables
+.SS Predefined Variables
+
+\*(TC predefines a number of variables.  The \'NAMESPACE\' variable we
+discussed in the previous section is one of them, but there are a number
+of others of which you should be aware.  Note that all predefined variables
+.B are relative to the root namespace.
+Except for the \'NAMESPACE\' variable, they are all Read Only and
+cannot be modified in your configuration file.
+
+The first group of predefined variables are called "System Variables".
+As the name implies, they provide information about the system on
+which you're running.  These are primarily useful when doing
+conditional tests (described later in this document).  For example,
+by doing conditional tests with System Variables you can have
+one configuration file that works on both Unix and Windows operating
+systems.  The System Variables are:
+
+.nf
+     Variable Name               Contains
+     -------------               --------
+
+    .MACHINENAME -    The name of the computer on which you are running.
+                      May also include full domain name, depending on system.
+
+    .OSDETAILS -      Detailed information about the operating system in use.
+
+    .OSNAME -         The name of the operating system in use.
+
+    .OSRELEASE -      The version of the operating system in use.
+
+    .PLATFORM -       The generic type of the operating system in use. 
+
+    .PYTHONVERSION -  The version of Python in use.
+.fi
+
+By combining these System Variables as well as the content of
+selected Environment Variables, you can create complex conditional
+configurations that "adapt" to the system on which a Python
+application is running.  For example:
+
+.nf
+
+   .if [.MACHINENAME] == foo.bar.com
+        BKU = tar
+
+   .else
+
+        BKU = [$BACKUPPROGRAM]
+
+   .endif
+.fi
+
+The other kind of predefined variables are called "Reserved Variables".
+\*(TC understands a number of symbols as part of its own language.
+For example, the string \'#\' tells \*(TC to begin a comment until
+end-of-line.  There may be times, however, when
+.B you
+need these strings for your own use.  In other words, you would like
+to use one of the strings which comprise the \*(TC language for your
+own purposes and have \*(TC ignore them.  The Reserved Variables
+give you a way to do this.  The Reserved Variables are:
+
+.nf
+     Variable Name               Contains
+     -------------               --------
+
+       DELIML                      [
+       DELIMR                      ]
+       DOLLAR                      $
+       ELSE                        .else
+       ENDIF                       .endif
+       ENDLITERAL                  .endliteral
+       EQUAL                       =
+       EQUIV                       ==
+       HASH                        #
+       IF                          .if
+       IFALL                       .ifall
+       IFANY                       .ifall
+       IFNONE                      .ifnone
+       INCLUDE                     .include
+       LITERAL                     .literal
+       NOTEQUIV                    !=
+       PERIOD                      .
+
+.nf
+
+For instance, suppose you wanted to include the \'#\' symbol
+in the value of one of your variables.  This will not work,
+because \*(TC interprets it as the beginning of a comment,
+which is not what you want:
+
+.nf
+    MyJersey = Is #23
+.fi
+
+So, we use one of the Reserved Variables to get what we want:
+
+.nf
+    MyJersey = Is [HASH]23
+.fi
+
+One word of warning, though.  At the end of the day, you still have
+to create variable names or namespace names that are legal.  You
+can't "sneak" illegal characters into these names using Reserved
+Variables:
+
+.nf
+    foo = [DOLLAR]MyNewNamespace   # No problem
+    NAMESPACE = [foo]              # No way - namespace cannot start with $
+.fi
+
+
 
 .SS The \'.include\' Directive