Differences between "Auntie Wu" and "Wai" Pinyin

The difference between "Auntie Wu" and "Wai" pinyin: "Auntie Wu" is three syllables, and "Wai" is a disyllabic syllable composed of initial w and vowel ai. Hanyu Pinyin is a Latin scheme of Hanyu Pinyin officially promulgated by People's Republic of China (PRC), which was approved by the former China Language Reform Commission (now the State Language Commission) in the text reform from 1955 to 1957.