Audio codecs are software or hardware tools that compress and decompress digital audio files. They help reduce the file size for easier storage and transmission while maintaining sound quality. Common audio codecs include MP3, AAC, and WAV, each with its own strengths and weaknesses in terms of quality and compression efficiency. When audio is encoded using a codec, it transforms the original sound into a format that can be easily shared or streamed. Decoding reverses this process, allowing playback on various devices. This technology is essential for music streaming services like Spotify and Apple Music, ensuring users enjoy high-quality audio.