Server 1 is a basic form interface that triggers an action in the database
Server 2 allows the user to enter a custom nickname that will be stored in the database (everyone is the same user, though!)
Server 3 demonstrates extensibility of usernames - all users still use the same id, but the id is presented as a variable (not hard coded)
Server 4 converts Server 3 into a POST request
Server 5 ask for a profile number in the form; allows the user to set a nickname for a particular profile number