Javascript is an object-oriented programming language which - when combined with HTML - enables client-side interactive functionality within almost all modern web browsers.
We'll be using the Javascript shell included with Rhino as an interactive environment in which to experiment. Rhino is available at https://developer.mozilla.org/en/RhinoDownload. On Mac OS X, you might prefer to use Homebrew:
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Every function is itself an object, and every function object has an 'arguments' attribute which enables variable number of arguments