instance.rb

class Customer

	attr_reader :name 
	@class_variable = "hello"  #instance class varaible, cause self => customer.class

	def self.show
		@class_variable
	end

	def initialize(name) 
		@name = name   # @name instance variable, cause it's created when instance initialized 
	end

end


puts Customer.show

peter = Customer.new("Peter")
# peter.show #=> error, cause instances can't access to class methods
puts peter.name