A little example to show how *, +, -, / and so on are just methods

crazy_fixnum.rb

class Fixnum
  def +(other)
    self - other
  end

  def *(other)
    self / other
  end

  def ==(other)
    true 
  end 
end

puts " 2 + 2  = #{2 + 2}" 
puts " 10 * 5 = #{10 * 5}" 
puts " 7 == 2  #{7 == 2}" 
puts " 5 == 5  #{5 == 5}"