What is the name of Network Setup Assistant's window?

This is a somewhat common interface, and is generally used to move a user through a series of sequential operations. It can be found in Apple's Network Setup Assistant (System Preferences > Network > Assist Me > Assistance), in many third party .pkg installers, and in applications like VirtualBox. It has a Low Opacity (light) image as a background, with a translucent Text Field on it, with a visually distinct bottom row with the next and previous buttons. Here is an example: