The View menu is the eyes of Photoshop, helping you in navigating in your image file and influencing the way your preview works.
In practice, you will rarely need to use this menu, because you can very comfortably zoom in and out of your image by holding CTRL + SPACE and your left mouse button and then moving your mouse up or down.
(You can also of course use CTRL + PLUS or MINUS or holding ALT and using the mouswheel)
