As we shall see in coming chapters, the Strategy pattern resembles, at least superficially, several other patterns. For example, in the Strategy pattern we have an object—the context—that is trying to get something done. But to get that thing done, we need to supply the context with a second object—the strategy object—that helps get the thing done. Superficially, the Observer pattern works in much the same way: An object does something, but along the way it makes calls to a second object, which we need to supply.
