A forced oscillator is a system that vibrates due to an external periodic force. This force causes the oscillator to move at the frequency of the applied force, rather than its natural frequency. Common examples include a child on a swing being pushed or a tuning fork being struck. In physics, the behavior of a forced oscillator can be analyzed using concepts like resonance and damping. When the frequency of the external force matches the natural frequency of the oscillator, it can lead to large amplitude oscillations. This phenomenon is important in various applications, including engineering and music.