They're not the exact same, but they are very similar. Typically potstickers will have a thinner outer layer, while dumplings are not. Potstickers are also fried as one of the main cooking methods, whereas dumplings will not be fried to be cooked. A lot of people will interchange the two, as I have in this recipe in spots, but there is a difference between the two in terms of what you will find on a menu or order.