<SPAN style="mso-bidi-font-family: Arial">A quartz clock is a clock that uses an electronic oscillator that is regulated by a </SPAN><SPAN style="mso-bidi-font-family: Arial">quartz crystal to keep time. This crystal oscillator creates a signal with very </SPAN><SPAN style="mso-bidi-font-family: Arial">precise frequency, so that quartz clocks are at least an order of magnitude more </SPAN><SPAN style="mso-bidi-font-family: Arial">accurate than good mechanical clocks. Generally, some form of digital logic </SPAN>
<SPAN style="mso-bidi-font-family: Arial">counts the cycles of this signal and provides a </SPAN><SPAN style="mso-bidi-font-family: Arial">numeric time display, usually in units of hours, </SPAN><SPAN style="mso-bidi-font-family: Arial">minutes, and seconds. Since the 1970s, </SPAN><SPAN style="mso-bidi-font-family: Arial">they have become the most widely used </SPAN><SPAN style="mso-bidi-font-family: Arial">timekeeping technology. </SPAN>