I think one of the coolest sites to see in Las Vegas is the Fountains at the Bellagio. It truly is mesorizing to see at night time.

These fountains, also generally called musical fountains, appear to respond to music but have been programmed beforehand. The earliest of these 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 must still be 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.
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