Perl 5.7.3 and later ships with an adequate set of Chinese encodings, including the commonly used CP950, CP936 (also known as GBK), Big5 (alias for Big5-Eten), Big5-HKSCS, EUC-CN, HZ, and ISO-IR-165. However, the numbers of Chinese encodings are staggering, and a complete coverage will easily increase the size of perl distribution by several megabytes; hence, this CPAN module tries to provide the rest of them. If you are using perl 5.8 or later, Encode::CN and Encode::TW will automatically load the extra encodings for you, so there's no need to explicitly write use Encode::HanExtra if you are using one of them already.