There is a Unicode standard, see http://arstechnica.com/gadgets/2014/06/unicode-7-0-introduces-2834-new-characters-including-250-emoji/ http://arstechnica.com/g

There is a Unicode standard, see http://arstechnica.com/gadgets/2014/06/unicode-7-0-introduces-2834-new-characters-including-250-emoji/ http://arstechnica.com/gadgets/2014/06/unicode-7-0-introduce... which explains a lot about emoji. There is room for interpretation to what each drawing will look like in each implementations. The standard simply says something like: "Cloud With Lightning"