.NET remoting is replacement of DCOM. Using .NET remoting, you can make remote object calls, which lie in different Application Domains. As the remote objects run in different process client calling the remote object cannot call it directly. Therefore, the client uses a proxy, which looks like a real object.
When client wants to make method call on the remote object it uses proxy for it. These method calls are called as Messages. Messages are serialized using formatter class and sent to client channel. Client Channel communicates with Server Channel. Server Channel uses as formatter to deserialize the message and sends to the remote object.