Symbol (typeface)

Symbol is one of the four standard fonts available on all PostScript-based printers, starting with Apple's original LaserWriter (1985). It contains a complete unaccented Greek alphabet (upper and lower case) and a selection of commonly used mathematical symbols. Insofar as it fits into any standard classification, it is a serif font designed in the style of Times Roman.

Due to its non-standard character set, lack of diacritical characters, and type design inappropriate for continuous text, Symbol cannot easily be used for setting Greek language text, though it has been used for that purpose in the absence of proper Greek fonts. Its primary purpose is to typeset mathematical expressions.

The font was created by Adobe and has its own character encoding, with the Greek letters arranged according to similar Latin letters (Chi = C, etc.). The document describing the mapping to Unicode code points was created before several of the characters were added to Unicode, so the original mapping assigns several of the characters to the Private Use Area (PUA). A later version of the font by Apple uses more recently introduced Unicode code points instead. The table below mostly follows the Apple mapping.

The characters ®, ©, and ™ are encoded twice: one version has serifs, the other (highlighted in yellow) is sans-serif. The Adobe mapping uses PUA for all six characters to ensure that the presence or absence of serifs is observed, while the Apple font maps the serif versions to the standard Unicode code points and the sans-serif versions to PUA code points (but not the same ones Adobe used).

The character at 0x60 (highlighted in red) does not appear in Unicode. It is described in the Adobe map as "RADICAL EXTENDER", with the Adobe glyph name "radicalex", and is mapped to the PUA code point U+F8E5. It is an over-bar for extending the radical sign over the operands of the radical operator. Some versions of the font implement this as a non-spacing character so that it can be combined (like non-spacing diacritical marks) with the operands it covers.

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