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A record player is an obsolete device, generically similar to a CD player.  Records are disks of vinyl which have a single groove running spirally from the outside edge to the center.  The disk is rotated at constant RPMs (typically 33 or 45) by a mechanical spindle which pierces the disk through a premade hole.

The groove is inscribed with an amplitude-modulation image of the sound wave.  A diamond stylus mounted on an arm mechanically follows the waves in the groove; the stylus actuates either a piezoelectric crystal or an electromagnet.  The resulting signal is amplified to audibility.  Records allowed a fairly good sound quality, but were subject to mechanical wear and to clicks and pops resulting from dust on the record or scratches from the misuse of the stylus arm.