xLossless Decoder is a software application that decodes audio files compressed using the xHE-AAC codec. xHE-AAC is an advanced audio codec designed for high-quality audio compression, especially efficient at low bitrates. Essentially, the decoder takes the compressed xHE-AAC audio data and converts it back into a playable audio format. It[SQ]s crucial for playing back audio files encoded with this specific codec, as standard audio players may not support it.