The difference between Analog and Digital signals

Analog signals use continuously variable electric currents and voltages to reproduce data being transmitted. Digital signals use binary data strings to reproduce data being transmitted. Since data is sent using variable currents in an analog system, it is very difficult to remove noise and wave distortions during the transmission. For this reason, analog signals cannot perform high-quality data transmission. With digital signals noise and distortions have little effect, making high-quality data transmission possible. Here’s an analogy, consider a clock in which the second hand smoothly circles the clock face (analog) versus another clock in which the second hand jumps as each second passes (digital).