The representation of sound as a sequence of numerical values is commonly known as a raw audio file, with Pulse-code modulation (PCM) serving as the underlying format. Notable instances of this format include WAV files within the Microsoft Windows environment, generated by applications like "Sound Recorder," and AIFF files on Apple platforms. These files adhere to the PCM format, often accompanied by an initial header. This format finds widespread application in PC and mobile device audio protocols, requiring voltage levels between 1.8V and 3.3V and relying on signals such as CLK (clock) and Data for communication.