Sometimes you know what the types look like but not in detail. For instance, you know you need a structure with several named properties, but you don&#x27;t commit to a type for some of them. You can have a fairly deep idea about the object model: what kinds of classes there are and how they connect, yet be loose about some of the lower level details.<p>You have types in the dynamic realm. Only, you&#x27;re not restricted to executing nothing but consistently typed programs.