VECTORS
They the same as arrays except for the fact that they are instances of the java.util.Vector class and they can change in length. Many methods are provided within the Vector class. Some are shown below.

Example
    private static Vector v = new Vector();
    private static Vector w = new Vector();
    String[] names = {"Mary","Paul","William","Susan"};
    v.addAll(Arrays.setList(names));
    v.add("David");
    w=(Vector)v.clone();
    w.set(3,"Ruth");