A quartz clock is a timekeeping device. Its main component is a very stable quartz oscillator. The oscillation frequency generated by the quartz oscillator is extracted and used to drive the clock to indicate the time; this is what makes a quartz clock. The best quartz clocks can keep time accurately to one ten-thousandth of a second per day, meaning they would only be off by one second in approximately 270 years. However, with today's advanced science, such quartz clocks have been superseded by other, more precise types of clocks.
Quartz crystals have an interesting property: when a positive current is applied to one side and a negative current to the other, the side with the negative current will contract and bend into a U-shape. If positive and negative currents are alternately applied to both sides of the quartz crystal at regular intervals, the crystal will oscillate. Quartz crystals keep time based on this oscillation. The quartz crystal built into a personal computer oscillates 14,318,180 times per second. This is the working principle of a quartz clock.
