The Unicode Standard

The Unicode Standard is the technical specification maintained by the Unicode Consortium that assigns a code point and a reference glyph to every character a computer can display, from ordinary letters to runic, ogham, Yijing trigram and hexagram, alchemical and astronomical symbols. It is the working authority on which character is which, an authoritative technical register rather than a subject matter scholarly work, and this atlas treats it as top tier precisely because there is no more definitive answer to what a given symbol's standardized identity is. It is the right citation for a symbol's code point, name and standardized form. It says nothing about a symbol's history, meaning or use within any tradition, which needs its own separate scholarly source.