# Why are some option values symbols, other strings?

Is there a rationale, beyond historical accident, why some Mathematica option values are strings, while others are symbols?

It seems natural that some value spaces, e.g. named color schemes, are so numerous and only applicable to ColorData, e.g. ColorData["HTML"] and so should be strings.

On the other hand wouldn't it make more sense if "XAxis" in PairedHistogram[..., BarOrigin -> "XAxis"] were a built in symbol to be shared as an option value across composite graphics functions?

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Related question –  Leonid Shifrin Mar 27 '13 at 21:33
Thanks for the link. –  alancalvitti Mar 27 '13 at 21:35
Btw, strings almost always work even when the option is a symbol –  Rojo Aug 3 at 3:05

Talking about documentation and options, I still couldn't figure out how to use the "EdgeLayout" suboption of GraphLayout ... see here –  Szabolcs Mar 27 '13 at 21:44