D-Bus has use inter-process communication
Communications model
D-Bus was conceived as a generic, high-level inter-process communication system. To accomplish such goals, D-Bus communications are based on the exchange of messages between processes instead of "raw bytes". D-Bus messages are high-level discrete items that a process can send through the bus to another connected process. Messages have a well-defined structure (even the types of the data carried in their payload are defined), allowing the bus to validate them and to reject any ill-formed message.
In this regard, D-Bus is closer to an RPC mechanism than to a classic IPC mechanism, with its own type definition system and its own marshaling.
The bus supports two modes of interchanging messages between a client and a service process: