Bopomofo / BPMF / Zhuyin Fuhao

bpmf

An early version of zhuyin fuhao. Note the symbols, no longer used, for v and gn. Also note how it is labeled in gwoyeu romatzyh as Gwoin Tzyhmuu (Guóyīn Zìmǔ).

Zhuyin fuhao, or bopomofo (BPMF) as it is often called, is of course not a romanization system, because it does not use the roman alphabet (a, b, c, etc.). But as it is the standard pedagogic tool for teaching Mandarin to Taiwanese children, it is well known in Taiwan and works well as a reference system, along with hanyu pinyin.