Microsoft Azure Service Bus is the main component in Microsoft Azure Stack that enables us to connect Dynamics 365 with Microsoft Azure. Through Azure Service Bus we can pass the details of an operation performed inside Dynamics 365 to multiple applications that are listening to it and can read and process that information.
Azure Service Bus can be defined as a cloud messaging service that runs in Microsoft's Azure Data Center. Azure Service Bus enables us to connect different applications, services or devices that are hosted in the cloud or on-Premises inside the firewalled networks. It can be used to connect different line-of-business (LOB) applications, tablets, phones or even any household appliances or sensors. This Azure Service Bus supports two different communication mechanisms: brokered messaging (queues, topics, and subscriptions) and relay service.