Inner/Outer class obj.new

Inner/Outer class obj.new

This is the example of member inner class that is invoked outside a class.
//Program of memeber inner class that is invoked outside a class
class Outer{
private int data=10;
class Inner{
void msg(){
System.out.println("Data: " + data);
}
}
}
class Test{
public static void main(String args[]){
Outer obj=new Outer();
Outer.Inner in = obj.new Iner();
in.msg();
}
}
Could someone explane this line of code Outer.Inner in = obj.new Iner();,
what does it mean obj.new Inner(); ?