D-Bus is a message bus system, a simple way for applications to talk to one another. The libdbus-1 library provides low-level API. The dbus-glib-1 library provides C-language bindings for using D-Bus with a higher-level approach. The higher level approach is possible because GLib defines a main loop, an object/type system, and an out-of-memory handling policy (it exits the program).
D-Bus supplies both a system daemon (for events such as "new hardware device added" or "printer queue changed") and a per-user-login-session daemon (for general IPC needs among user applications). Also, the message bus is built on top of a general one-to-one message passing framework, which can be used by any two apps to communicate directly (without going through the message bus daemon).
30 /usr/lib/libdbus-1.so D-Bus library
30 /usr/lib/libdbus-glib-1;.so D-Bus GLib bindings library
30 /usr/share/doc/dbus/ Location of developer documentation
dbus-binding-tool(1), dbus-cleanup-sockets(1), dbus-daemon(1), dbus-launch(1), dbus-monitor(1), dbus-send(1), dbus-uuidgen(1), libglib-2.0(3), attributes(7), gnome-interfaces(7)