Analog circuits are electronic circuits that process continuous signals, which can vary smoothly over time. These circuits use components like resistors, capacitors, and transistors to manipulate voltage and current. Common examples of analog circuits include audio amplifiers and radio transmitters, where the goal is to amplify or modulate sound waves or radio frequencies. Unlike digital circuits, which operate using discrete values (like 0s and 1s), analog circuits can represent a wide range of values. This allows them to handle real-world signals more naturally, making them essential in devices such as televisions, microphones, and sensors that interact with the physical environment.