The medieval Occitan troubadour known as the Monk of Montaudon was a master of the enueg, “song of annoyance.” “I can’t stand a long wait,” he complains in one composition, written around 1200, “Or a priest who lies and perjures himself / Or an old whore who is past it, / And—by Saint Delmas—I don’t like / A base man who enjoys too much comfort.” The song goes on in this fashion for nine more verses.

Hoping to encourage hostages held by FARC during Colombia’s civil war, state negotiators commissioned a local producer in 2010 to create a pop song embedded with a Morse-code message and had it broadcast repeatedly on the radio in rebel-controlled areas. After the lyrics “Listen to this message, brother,” the code sounded as a synth interlude: “Nineteen people rescued. You are next. Don’t lose hope.”

Irving Berlin composed most of his songs in F-sharp major; the six sharp notes in the scale meant he could play the black keys of the piano almost exclusively. Eventually, for purposes of technical variety, he had a lever mechanism installed that allowed him to modulate into other keys without changing his playing.

In an 1899 treatise written while in exile, Vladimir Lenin critiqued the capitalist growth of Russian industries in which factory workers had replaced skilled craftsmen. Among his concerns was a shift toward the mass production of cheap accordions, which, he complained, “have nearly everywhere displaced the primitive string folk instrument, the balalaika.”