An ADC (Analog-to-Digital Converter) is an electronic device that converts continuous analog signals into discrete digital numbers. This process allows computers and digital systems to process real-world signals, such as sound, light, and temperature, which are inherently analog in nature. ADCs are essential in various applications, including audio recording, video processing, and sensor data acquisition. They enable devices like smartphones and cameras to interpret and manipulate analog inputs, making them crucial for modern technology. Common types of ADCs include successive approximation, sigma-delta, and flash ADCs.