A voice companding technique specified in the ITU-T G.711 Recommendation for pulse code modulation (PCM). This technique, which is used in the European digital hierarchy, converts 13-bit linear PCM samples into 8-bit compressed samples. Mu-law (-law) is a similar, but incompatible, companding technique used in the North American (T-carrier) and Japanese (J-carrier) digital hierarchies. In an international call, A-law is used if at least one of the national networks involved in the call uses A-law. See also companding, E-carrier, G.711, ITU-T, J-carrier, mu-law, PCM, and T-carrier.