UIView
A UIView represents a rectangular area of the screen that can hold UITextFields, UIButtons, UIImages, etc.
You would generally create a UIView in a UIViewController's loadView method.
Example
UIView *myView =
[ [UIView alloc]
initWithFrame:[[UIScreen mainScreen]
applicationFrame] ];
self.view = myView;
[myView release];
Displaying new views:
MyController *controller =
[[MyController alloc] init];
[self presentModalViewController:controller
animated:YES];
[controller release];
and to dismiss the controller:
[self dismissModalViewControllerAnimated:YES];
or use a UINavigational controller
[self.navigationController
pushViewController:myController
animated:YES];
[[self navigationController]
popViewControllerAnimated:YES];