Tongyong Pinyin (Chinese: 通用拼音; Tongyong Pinyin: Tongyòng Pinyin; Hanyu Pinyin: Tōngyòng Pīnyīn; literally "Universal/General Usage Sound-combining") was the official Romanization of Mandarin Chinese in the Republic of China (ROC) (Taiwan) between 2002 and 2008. The system was unofficially used between 2000 and 2002, when a new romanization system for the Republic of China was being evaluated for adoption. The ROC's Ministry of Education approved the system in 2002 but its use was not mandatory. Since January 1, 2009, Tongyong Pinyin is no longer official, due to the Ministry of Education's approval of Hanyu Pinyin on September 16, 2008.
Read more about Tongyong Pinyin: History, Adoption and Use, Taiwanese Language Variant, Arguments, Comparison Between Hanyu Pinyin and Tongyong Pinyin