This stand is a fits onto the right hand end of the PS4 and is secured by two rotating locks. It is fixed in place extremely securely. The design exactly matches the angular shape of the PS4 so that it looks like it was part of the original design.
It is possible to stand the PS4 up on end without this stand, but with it, it is much less likely to remain upright if it gets a small knock or if it gets tugged by one of the cables.
I personally think it is worth getting as it gives you the option of saving some space compared to having the console laying flat.