MP3 is a digital audio encoding format based on a form of lossy data compression. Also known as MPEG-1 Audio Layer 3, it is a common audio format for consumer audio storage and is a standard for transfer and playback of music on digital audio players. It was designed by the Moving Picture Experts Group and has been approved by ISO/IEC standard.
The lossy compression algorithm for MP3 has been designed to reduce the amount of data required to represent the audio recording and sound like an exact reproduction of the original uncompressed audio. An MP3 file can be constructed at higher or lower bit rates with the corresponding resulting quality.
The compression is achieved by reducing the accuracy of certain parts of sound that are beyond the auditory resolution ability of people, and the method is known as perceptual coding. The method makes use of psychoacoustic models in order to discard or reduce the precision of components that are less audible, and then efficiently records the remaining information.
The MP3 lossy audio data compression makes use of the principle of auditory masking that is a perceptual limitation of human hearing. The lossy encoding involves a trade-off between the amount of space used and the sound quality of the result. The bit rate can be set that specifies the kilobits that can be used by the file per second of audio. Lower bit rates provide lower audio quality and smaller file size and it works vice-versa with higher bit rates.