Message Queuing or what you can call as MSMQ itself is an asynchronous programming. This is because the clients does not wait for the server to read the data sent to it. But there is a difference between the MSMQ itself and the asynchronous programming. In MSMQ world, all the sender and recipient transaction can be occur in disconnected and connected method, while the asynchronous programming, the transaction can only occur in connected mode. Message Queuing is kind of email for application to application communication. But MSMQ has lots more features to offer, such as guaranteed delivery ,transactions,confirmatio ns, express mode using memory and so on. With MSMQ you can send,receive, and route messages in a connected or disconnected environment.