Lossless audio formats (such as TTA and FLAC) provide a compression ratio of about 2:1

Lossless compression formats do not remove information from the audio, Where as Lossy compression formats do ( IE MP3,AAC ).

FLAC is also a popular archive format for owners of CDs and other media who wish to preserve their audio collections. If the original media is lost, damaged, or worn out, a FLAC copy of the audio tracks ensures that an exact duplicate of the original data can be recovered at any time.