A frequency divider is an electronic circuit that reduces the frequency of an input signal to a lower output frequency. It works by dividing the number of cycles of the input signal, allowing for precise control of timing and synchronization in various applications. Frequency dividers are commonly used in digital electronics, such as in clocks and timers. These circuits can be implemented using different technologies, including flip-flops and counter circuits. Frequency dividers are essential in communication systems, where they help manage signal frequencies for efficient data transmission and processing.