- (void) goBack:(NSNotification *) notification
{
      // [self.navigationController popViewControllerAnimated:YES];
     //  [self dismissViewControllerAnimated:YES completion:nil];
      [self.navigationController popToRootViewControllerAnimated:TRUE];
}

[self.navigationController popToRootViewControllerAnimated:TRUE];

[self.navigationController popViewControllerAnimated:TRUE];

[self.navigationController popViewControllerAnimated:YES];

[self.navigationController popToRootViewControllerAnimated:YES];

[self.navigationController popToViewController:viewControllerObject animated:YES];

- (IBAction)backButton:(id)sender
{
bookdescriViewController *previosVC = [[bookdescriViewController alloc]init];
[self.navigationController popViewControllerAnimated:YES]; // go to previous vc
[self.navigationController popToRootViewControllerAnimated:YES]; // go to root view controller
[self.navigationController popToViewController:previosVC animated:YES]; // go to any view controller
[previosVC release];
}

[self.navigationController dismissViewControllerAnimated:YES completion:NULL];

navigationController?.popViewControllerAnimated(true)

- (void) goBack:(NSNotification *) notification
{
   if(!self.YOrView.isHidden)
      self.YOrView.hidden = YES;
}