Wade–Giles is a romanization system for the Mandarin Chinese language. Taiwan has used Wade–Giles for decades as the de facto standard. Wade–Giles spellings and pinyin spellings for Taiwanese place names and words long accepted in English usage are still used interchangeably in English-language texts.
A feature of the Wade–Giles system is the representation of the unaspirated-aspirated stop consonant pairs using left apostrophes: p, pʻ, t, tʻ, k, kʻ, ch, chʻ. This leaves b, d, g, and j available for the romanization of Chinese languages containing voiced consonants (see voice (phonetics)), such as Southern Min whose century-old Peh-oe-ji (often called Missionary Romanization) is similar to Wade–Giles.