 So, you just saw how port numbers actually help the communication between one application and the other by assigning these port numbers, the applications are able to determine which packet belongs to which application and also we saw that port numbers have also been efficiently used in another aspect which was called network address translation. Now, here you could use the same IP address, but use a different port number for a different communication and by using that you could just use the same IP address for a lot of communication which we call the port address translation. So, this helps you in using one single global IP address for multiple communications. So, now is the right time for a quiz.