An appliance, such as the Sun Ray appliance, is an X display device that requires no administration. There is no CPU, fan, disk, and very little memory. An appliance is connected to a Sun display monitor. However, the appliance user's desktop session is run on a server and displayed back to the user.
The X environment is set up automatically for the user and has the following characteristics:
Relies on a server to access other file systems and software applications
Provides centralized software administration and resource sharing
Contains no permanent data, making it a field-replaceable unit (FRU)