One of the most common audio formats. The format was developed by Microsoft (in collaboration with IBM) and usually stores uncompressed audio data with pulse-code modulation, but it can be used to store sound processed with other audio codecs.

This format was originally intended for voice compression and is able to change the bit rates of encoded audio data. AMR is actively used for encoding and decoding voice while its being transmitted over network channels. The format allows one to consider network capacity and adapt it to channel loads. Due to this, the voice quality is practically undiminished.