Advanced Audio Coding (AAC) is a digital audio signal format that uses a lossy compression algorithm. It removes some audio data to achieve the maximum possible compression, obtaining a result that is very close to the original track.
It is the audio codec of choice for wireless, Internet and digital broadcast radio, and is at the core of 3GPP, 3GPP2 and MPEG-4. It uses a variable bit rate, adapting the number of bits per second to encode the audio, depending on the complexity encountered at each moment of the transmission.
Its performance surpasses that of MP3, since the latter only works better on small files with lower resource requirements. The AAC format supports multichannel sound and can reach sampling frequencies of 96 khz, twice as high as MP3. In addition, the sound quality of AAC is much higher, suffering much lower bit loss.