When should we implement Serializable interface?
<pre><code>package 

public class Contact implements Serializable  {

 private String name;
 private String email;


 public String getName() {
        return name;
    }

    public void setName(String name) {
        this.name = name;
    }

    public String getEmail() {
     return email;
    }

    public void setEmail(String email){
     this.email = email;
    }


}
</code></pre>

<ol>
<li>When should i implment Serializble
interface?  </li>
<li>Why do we do that?</li>
<li>Does it give any advantages or security?</li>
</ol>
