In addition to Unicode (with the set of CJK Unified Ideographs), local encoding systems exist.
In contrast to the situation with Japanese, there has been relatively little overt opposition to Unicode, which solves many of the issues involved with GB and Big5.
Unicode is widely regarded as politically neutral, has good support for both simplified and traditional characters, and can be easily converted to and from the GB and Big5.
The Big5 family of character encodings start with the initial definition by the consortium of five companies in Taiwan that developed it.
Quite a few vendors as well as official extensions exist, of which ETEN, HKSCS (Hong Kong) and Big5-2003 (as a part of CNS 11643 by Taiwan) are the most well-known ones.
Thus simplified to traditional conversion often requires usage context or common phrase lists to resolve conflicts.
This issue is less of a problem with newer standards such as GBK, GB 18030 and Unicode, which have separate code points for both simplified and traditional characters.