Wikipedia
Discuz!
Discuz! is Internet forum software written in PHP and developed by Comsenz Technology Co., Ltd . It supports MySQL and PostgreSQL databases. It is the most popular Internet forum program used in China.
Discuz! is free of charge for private uses. A license that allows commercial use costs about 3000 RMB. The software is officially available in Chinese. It was officially developed in an English version also, but the development stopped due to financial reasons. There are unofficial English and other language versions provided by certain websites.