Simplified Wade is a modification of the Wade-Gilesromanization system for writing Mandarin Chinese. It was devised by the Swedish linguistOlov Bertil Anderson, who first published the system in 1970. Simplified Wade uses tonal spelling: in other words it modifies the letters in a syllable in order to indicate tone differences. It is one of only two Chinese romanization systems that indicate tones in such a way (the other being Gwoyeu Romatzyh). All other systems utilize diacritics or numbers to indicate tone.
One of the important changes that Anderson made to Wade-Giles to was to replace the apostrophe following aspirated consonants with an <h>.[1] This modification, previously used in the Legge romanization, was also adopted by Joseph Needham in his Science and Civilisation in China series.[2] The table below illustrates the spelling difference.