Concepts of Service Reference in Silverlight 5 Application

Question

Hi all.....

I need help in Service Reference in Silverlight Application.

I need the answers to the following questions:

1)What files are created when we add a service reference to a silverlight application?

2)What changes are made when we update the service reference ?

3)Why do we get errors like - TimeOutException, FailedToUpdateServiceReference, etc?

4)Difference between OperationContract and DataOperations ?

5)What is the Execution Process of serviceReference ?

etc...

Please help in getting the service concepts clear in silverlight application....

Thanks all in advance !!