The different standard code tables require translator applications that allow the conversion of a document encoded in one code system to a different code system. A translation can either be total, i.e. for each character of one alphabet there exists a character in the other alphabet, or partial, i.e. there exist characters in one alphabet for which there is no character in the other alphabet. A translation can be bidirectional or unidirectional. In partial translations, information is lost: either because some characters cannot be represented at all, or because the meaning of a character in one alphabet is different from that in the other alphabet.