Sinusoidal Pulse Width Modulation (SPWM) is a specific type of PWM where the modulating signal is a sine wave. It involves generating a series of pulses with varying widths that correspond to the amplitude of a sinusoidal signal. By controlling the pulse width, SPWM allows precise control of the voltage or current supplied to a load, reducing harmonics and improving the efficiency of power electronics systems. SPWM finds applications in motor drives, inverters, power converters, and audio amplifiers, among others.