When you receive your confirmation, Carnival does not say what type of cabin quote you have. You might want to write these down. Look in the upper right hand corner of the email and you will see "Category:" followed by a number. Here is the Key:
Interior cabins begin with the numbers "1" or "4";
Ocean View cabins will have the number "6";
Balcony cabins will be "7" or "8";
Ocean Suites will be "OS";
Grand Suites will be "GS".