Creating domain services

Now that we have the Silverlight application, the database, and the Entity Data Model, we will now create the Domain Service class for the Entitites. I am not totally sure what the Domain Service will do, but I think it provides classes and API's which the application can call from the client side Silverlight control.

I right clicked on the 'Services' tree node, and selected, 'Add new'. Then I selected the 'Domain Service' class template, gave it a name, and selected the Entities we want to expose in the Domain Service.

Some noteworthy points and questions:

1. What exactly is a domain service class?
2. The domain service class extends the class 'LinqToEntitiesDomainService'
3. The domain service class has the [EnableClientAccess()] annotation. Is this really an annotation, or is it something else. The () seem to suggest that it is invoking some method, so this might be a special syntax to specify that some internal method needs to be invoked at some time. Is this at build time, runtime ? Not quite sure.
4. The entire namespace is enclosed in {}
5. A file called EventManagerDomainService.metadata.cs was also created. This file has a bunch of partial classes. Need to find out what partial classes are.