Everything in java is an OBJECT
String is an object so are the classes
String is a class  but also, you use strings  to declare data types
eg: String name="Baglan"
You make this decleration inside a class
eg:
Public MyClass {
String name="Baglan"
....
...
}
Classes have attributes  (properties) and they have methods  which determine the
behavior of that class
Good luck
If you need further explanation you can refer to
www.java.sun.com