The dbus-daemon provides a message bus daemon which programs can use to exchange messages with one another. dbus-daemon is implemented with the D-Bus library which provides one-to-one communication between any two applications.

For extended information, see the man page for dbus-daemon.

Credentials such as user name and password for various programs and websites are stored securely using the gnome-keyring-daemon. This information is written into an encrypted file called the keyring file and saved in the user's home directory.

For extended information, see the man page for gnome-keyring-daemon.

The gnome-session program is responsible for running the GNOME desktop environment with help of a display manager such as GDM, LightDM, or NODM. The default session for the user is set at the time of system installation by the system administrator. gnome-session typically loads the last session that ran successfully on the system.

For extended information, see the man page for gnome-session.

The gnome-settings-daemon handles settings for a GNOME session and for all programs that are run within the session.

For extended information, see the man page for gnome-settings-daemon.

gnome-shell provides the core user interface functionality for GNOME such as launching programs, browsing directories, viewing files and so on.

For extended information, see the man page for gnome-shell.

PulseAudio is a sound server for Linux, POSIX and Windows systems that lets programs output audio via the Pulseaudio daemon.

For extended information, see the man page for pulseaudio.