A String variable is basically just words. Like in: System.out.println("This is a string");
So if you declare a string variable, you type: String nameOfString = "Words of the String";
For self check 2.6, it is asking for you to say what type of variable that it uses. I didn't use String in it when I first did it. If it's a string variable, it has to consist of words. We had only gone over int and double in class, but there are others covered in the book such as boolean and string and character (char).