D-Bus is a message bus system, a simple way for applications to talk to one another. For more information on D-Bus, see http://www.freedesktop.org/wiki/Software/dbus.
dbus-glib is a deprecated API for use of D-Bus from GLib applications. Do not use it in new code.
Since version 2.26, GLib's accompanying GIO library provides a high-level API for D-Bus, "GDBus", based on an independent reimplementation of the D-Bus protocol. The maintainers of D-Bus recommend that GLib applications should use GDBus instead of dbus-glib.