I recently looked up the character 什 on zhongwen.com, and it showed me three pronunciations, with abbreviations I don't understand. It looks like this:

shí, [國] shé, [普] shén

I'm not what these 國 and 普 notations are referring to. Does anyone here know? I have the feeling that 國 refers to the Taiwan dialect while 普 refers to mainland Mandarin. If that's the case, to which dialect does shí belong?

Sorry for such a n00b question.