Linux Kernel Launches Hardware Management Features - page 2
Preparing for Liftoff
D-Bus can be thought of as a central communications mechanism between Linux applications. If you want to sound properly geeky, it's an IPC (Interprocess Communication Facilities) mechanism for sending and receiving messages. Linux used to rely on sockets, pipes, filesystems, and shared memory for communications between applications. It wasn't very efficient or flexible, and without a common base communications system it meant developers spent a lot of energy re-implementing the same thing in all manner of different ways.
Prior even to Linux's creation, some of the problems the Linux developers would eventually face were well known to developers. An industry consortium called OMG (Object Management Group) came up with CORBA (Common Object Request Broker Architecture) as a solution to the problem of applications interoperability, and apparently a host of other problems as well. Some time later, the KDE team invented DCOP (Desktop COmmunications Protocol). There were other attempts to create a standard message platform, and then along came the D-Bus, a Freedesktop.org project designed from the ground up to be the universal, standard messaging platform for the Linux and Unix desktop. (There is even a Windows port in the works, windbus.) D-Bus is used on most Linux distributions these days.
D-Bus supplies a global system daemon and per-user session daemons. Take a look in
/etc/dbus-1 to see what applications are using D-Bus on your system. Some of the more common examples are HAL, udev, NetworkManager, CUPS, and Yum.