audio

streaming services use compression methods to reduce file size for convenience in sending and storage.

codec

a codec is a method of compressing and decompressing digitized sound. MP3 is an example of a digital audio codec. The greater the compression, the more sonic details are lost. Extremely high and low frequencies usually get discarded with even slight compression.

the bitrate, or average amount of data required per second of music, determines the audio resolution of a music file. The higher the number of kilobits per second (kbps), the closer in sound quality the file is to the original source, and the larger the file size. CD bitrate is 1411 kbps. MP3 format can range from 96 to 320 kbps. Spotify delivers audio with a bitrate 96 kbps (on normal setting).

Standard lossy 320 kbps

MP3 is a lossy compression format. Some frequencies are lost in the encoding process, and can't be restored by reconverting the file to its original format.

HIFI lossless 1411 kbps

FLAC is a lossless compression format. this provides a compression ratio of 2:1 so files take up half the space. lossless audio presents all of the information to you that was in the original uncompressed files. lossless compression is a class of data compression algorithms that allows the original data to be completely reconstructed from the compressed data.

the bitrate of a lossless file is 1411 kbps. this is 4X the audio quality of an MP3 file (with a bitrate of 320 kbps). lossless audio is always better than 320 kbps based on its quality.