Previous transcription schemes sought to split the difference with the result that they achieved neither goal perfectly.
Wylie transliteration was designed to precisely transcribe Tibetan script as written, which led to its acceptance in academic and historical studies.
In the Wylie system, these are distinguished by inserting a period between a prefix g and initial y. E.g. གྱང "wall" is gyang, while གཡང་ "chasm" is g.yang.
However, these schemes were often applied inconsistently, and usually only when the word would normally be capitalised according to the norms of Latin text (i.e. at the beginning of a sentence).
The Tibetan and Himalayan Library at the University of Virginia developed a standard, EWTS—the Extended Wylie Transliteration Scheme—that addresses these deficiencies systematically.