The second way is that any object can be a prototype. It can have functions (which act like methods), it can have other values (like numbers, booleans, objects, or strings). It can be an object you're using for something else: An account, a view, a DOM object if you're in the browser, anything. "Classes" are objects in most "classical" languages, but they are a special kind of object. In JavaScript, prototypes are not a special kind of object, they're just objects.