The Base consists of the motor, heater, and controls.  The heater keeps the chocolate melted while the motor turns the auger (see below for more info on the auger).

 

The Tiers are just that - Tiers that the Chocolate flows over.

 

The Auger looks a corkscrew.  The Auger sets in the center of the tiers.  The motor rotates the Auger and brings the melted Chocolate from the base of the Fountain to the top of the tiers.  When the Chocolate reaches the top of the tier, the Chocolate overflows & cascades down over the tiers in a continuous stream of Chocolate and back into the base of the Fountain. 

 

The Chocolate Fountain runs continuously at the event.  The Chocolate level is simply monitored and additional Chocolate can be added so that the Chocolate flow runs uninterrupted.