The most popular school, Common Wu Pinyin (通用吴语拼音), was developed by amateur language clubs and local learners.
There are two competing schemes; both adhere to the International Phonetic Alphabet (IPA) and are very similar to each other.
This school of English-based Latin orthographies was developed by Western missionaries in the late 19th and early 20th centuries and used to write Bible translations and other educational texts.
[2] Another school is the Latin Phonetic Method (吴语拉丁式注音法, French-Wu or Fawu [法吴]).
[3][4] The final, and least used school, is developed by modifying Hanyu pinyin as sanctioned by the State Council.