title: How to save multiple user details in user defaults?
body: <p>I got a task to store multiple user details.</p>
  
  <pre><code>@IBOutlet weak var userName: UITextField!
  
  @IBOutlet weak var email_id: UITextField!
  
  @IBOutlet weak var password: UITextField!
  </code></pre>
  
  <p>I know in user defaults we can store a value for a particular key and retrieve it but i would like to know how to save multiple values. like the key should be the email_id i have mentioned above and all the three fields should be its values, also i need to maintain all the details even if there is n number of users.</p>