In physics, sound is a vibration that typically propagates as an audible wave of pressure, through a transmission medium such as a gas, liquid or solid.
Doctor: It plays music. What's the point of that? Oh, with music, you can dance to it, sing with it, fall in love to it. Unless you're a Dalek of course. Then it's all just noise.
Doctor Who Evolution of the Daleks (2007), written by Helen Raynor.
A thousand trills and quivering sounds In airy circles o'er us fly, Till, wafted by a gentle breeze, They faint and languish by degrees, And at a distance die.
It makes unavoidably necessary an entirely new organization of society in which production is no longer directed by mutually competing individual industrialists but rather by the whole society operating according to a definite plan and taking account of the needs of all.
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