1. View all parent class of objects
     Use "ancestors" method to find all parent class.
     eg: "string".class.ancestors
     output: => [String, Comparable, Object, Kernel, BasicObject]
2. Add new method to a class without editting existing file
    Test.send(:define_method,"type_name") do
      puts "Coding Test"
    end
    puts t.type_name
3.