The waltz was a dance originating in the late 18th century on the planet Earth, usually accompanied by a specific genre of music.
Kevin and Rishon Uxbridge often used to waltz to the music of their old music box. Uxbridge used the waltz music from the music box to block Deanna Troi's telepathic abilities. (TNG: "The Survivors")
In 2369, Miles O'Brien compared working with the computer of the USS Enterprise-D to simply dancing a waltz. This was in contrast to working with the computer of Deep Space 9, which he compared to participating a rigorous wrestling match. (DS9: "The Forsaken")
Famous waltz composers included Johann Strauss II and Johannes Brahms.