"Ajax applications can seem magical at first, but the process of developing the applications is straightforward, thankfully. For every Ajax interaction, you must create an endpoint (to borrow a term from our Web service friends) on a server and client-side code to call that endpoint. You must also create all the code for serializing the data going between the client and server. These server endpoints can be generic services, maybe even a RESTful one at that. However, they are more often very specific to the needs of the client. Sometimes you should avoid tight coupling, but sometimes you should embrace it. For the latter cases, DWR is a turnkey solution. It lets you declaratively expose server-side code as an Ajax endpoint, generating all the plumbing for you auto-magically. Now, take a look at a specific example to see how DWR works."
