From The Art and Popular Culture Encyclopedia
In filmmaking, dubbing or looping is the process of recording or replacing voices for a motion picture. The term most commonly refers to voices recorded that do not belong to the original actors and speak in a different language from the one in which the actor is speaking. "Dubbing" also describes the process of an actor re-recording lines they spoke during filming that must be replaced to improve audio quality or reflect dialog changes. This process is called automated dialogue replacement, or ADR for short. Music is also dubbed onto a film after editing is completed.
Foreign-language films, videos and sometimes video games are often dubbed into the local language of their target markets to increase their popularity with the local audience by making them more accessible. Dubbing is common both in theatrically released film and in television series, including Hollywood series and serialized Japanese anime that have received foreign distribution.