Let's suppose you have a well-educated user of your Person class, someone who has read the docs that explain the prescribed interface. Here's how they might use the Person class:
$him = Person->new(); $him->name("Jason"); $him->age(23); $him->peers( "Norbert", "Rhys", "Phineas" );
push @All_Recs, $him; # save object in array for later
printf "%s is %d years old.\n", $him->name, $him->age; print "His peers are: ", join(", ", $him->peers), "\n";
printf "Last rec's name is %s\n", $All_Recs[-1]->name;
As you can see, the user of the class doesn't know (or at least, has no business paying attention to the fact) that the object has one particular implementation or another. The interface to the class and its objects is exclusively via methods, and that's all the user of the class should ever play with.