Audio can be stored uncompressed, as with .aiff and .wav files. Lossless compression schemes, as used in .flac files, preserve the original sound quality by only removing unnecessary and redundant data. MP3, by far the most popular audio format, removes data using a lossy scheme which results in a slight loss of audio quality but significant compression. The AAC format is capable of better audio quality than MP3 in the general bit rate range, at the cost of less compression ability.