Improve Prototype Javadoc

prototype/src/main/java/com/iluwatar/prototype/App.java

@@ -2,9 +2,14 @@ package com.iluwatar.prototype;
 
 /**
  * 
- * In Prototype we have a factory class ({@link HeroFactoryImpl}) producing objects by
- * cloning the existing ones. In this example the factory's prototype objects are
- * given as constructor parameters.
+ * The Prototype pattern is a creational design pattern in software development. It is 
+ * used when the type of objects to create is determined by a prototypical instance, 
+ * which is cloned to produce new objects. This pattern is used to:
+ * - avoid subclasses of an object creator in the client application, like the abstract factory pattern does.
+ * - avoid the inherent cost of creating a new object in the standard way (e.g., using the 'new' keyword)
+ * <p>
+ * In this example we have a factory class ({@link HeroFactoryImpl}) producing objects by
+ * cloning the existing ones. The factory's prototype objects are given as constructor parameters.
  * 
  */
 public class App {