How does a bath tub diverter work to control the flow of water between the tub spout and the shower head?

A bath tub diverter is a valve that controls the flow of water between the tub spout and the shower head. When the diverter is turned or pulled, it redirects the water flow from the tub spout to the shower head, or vice versa. This allows you to easily switch between filling the tub and using the shower without having to adjust the water temperature each time.