A musical fountain, also known as a dancing fountain, is a type of animated fountain for entertainment purposes that creates an aesthetic design (including three-dimensional images). This is achieved by employing the effects of timed sound waves and timed light (including laser) against water particles. The water refracts and reflects the light, and in doing so, three-dimensional images can be produced.
Installations can be large scale, employing hundreds of water jets and lights, and costing into the millions of dollars, or in smaller household forms, where a budget of one thousand dollars is feasible. Musical features tend to be complex, and require a degree of mechanical, hydraulic, electrical, and electronic components out of view that might be as impressive to its audience as the show itself.
The earliest musical fountains were played manually by a live operator, who usually controlled pumps or valves and sometimes lights by way of switches on a control panel. Music was almost always live. Later, choreography could be prerecorded on a punched paper card which was scanned by a computer; and even later, it could be recorded on magnetic tape or, in the most modern shows, on a CD along with the music. Even so, the choreography is still usually painstakingly programmed by hand, some types of shows being played live from a control console and connected to a computer that records the operator's actions for later automatic playback. Recent advances in technology provides for unattended automatic choreography that can rival manual programming.