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Thank you for your response. It doesn't really clear things up for me though. Perhaps I need a much better understanding of JS but what's the point of it? How does it apply to the whole function at hand? What purpose does it serve?
Good afternoon all and forgive me if this has already been asked, I did search the forums and couldn't find an answer to my question which is:

At the top of the javascript code in listing 1.5 (chap1) the first line is:

var spa = (function($)){


Being fairly new to javascript I don't understand what the passing of the '$' means into the function. If somebody would be good enough to give this novice a clue I'd very much appreciate it. I understand the rest of it just fine.
Thanks.