Final answer:
A CD player uses a laser to detect bumps and pits on the surface of a CD, which correspond to the binary code needed to interpret the stored digital information.
Step-by-step explanation:
Lasers and mirrors in a compact disc (CD) player read digital information on a CD by interpreting variations in reflections of a laser beam. The data on a CD is encoded in the form of small "bumps" and "pits" on the CD surface which represent binary code. When the CD player's laser light strikes a bump, it reflects back to a sensor and is interpreted as a '1'. In contrast, when the light strikes a pit, it destructively interferes, and no light is reflected back. Thus, the absence of reflected light is interpreted as a '0'. Through this binary encoding, a large information capacity is made possible. The process is precise due to the coherent light being able to focus on such a small spot. Eventually, the binary code is converted to an analog signal to produce sound.