Added a section on single inheritance

src/classes-and-objects.pod

@@ -348,6 +348,41 @@ the various other dependencies in order, giving the output:
     making dinner
     eating dinner. NOM!
 
+=head1 Inheriting the Farm
+
+Object Oriented Programming provides the concept of inheritance as one of the 
+mechanisms to allow for code reuse.  Perl 6 supports the ability for one class 
+to inherit from multiple classes.  When a class inherits from another class it
+acquires all of the attributes and methods of the base class.
+
+=begin programlisting
+
+class Farmer
+{
+   has $.farm is ro;
+
+   method plant_crops( Str $crop )
+   {
+      "Planting some $crop at the farm"
+   }
+}
+
+class FarmerKid is Farmer
+{
+}
+
+=end programlisting
+
+Now all the objects of type FarmerKid will inherit the base class' farm 
+attribute and plant_crops method as though they were declared on FarmerKid.
+
+=begin programListing
+
+my $fk     = new FarmerKid( farm => 'across from the dairy');
+
+$fk.plant_crops('wheat');
+
+
 =head1 Exercises
 
 B<1.> The method C<add-dependency> in C<Task> permits the creation of I<cycles>