What is dynamic keyword used for

Question :What is dynamic keyword used for?
Answer :Dynamic classes, which allow you to programmatically add new properties and behavior to
classes during the run-time. Just add the magic keyword dynamic to the class definition:
dynamic class Person {
var name:String;
}
Now let’s add dynamically two variables name and age and the function printme() to the object of
type Person:
Person p= new Person();
p.name=”Joe”;
p.age=25;
p.printMe = function () {
trace (p.name, p.age);
}
p.printMe(); // Joe 25