A crystal oscillator uses the mechanical resonance of a piezoelectric crystal, commonly quartz, to produce a stable and predictable electrical oscillation. Its frequency characteristics make it useful as a timing and frequency reference in electronic systems, including computers, communication equipment, measurement instruments, and embedded devices.
Piezoelectricity is the property of certain materials to generate an electrical response when subjected to mechanical stress. The effect results from changes in charge distribution within the material and enables conversion between mechanical and electrical energy, with applications in sensors, actuators, ultrasonic transducers, frequency control, and other electromechanical systems.