2. Why Iffy matters?
l To avoid variable hoisting from within blocks,
protect against polluting the global environment
and simultaneously allow public access to
methods while retaining privacy for variables
defined within the function.
Additional information @https://en.wikipedia.org/wiki/Immediately-invoked_function_expression
8. Summary
lWell these are just syntactic sugars. The reason
to use is to avoid variable conflicts and use
namespacing
lDetailed discussion
@http://stackoverflow.com/questions/3755606/what-
does-the-exclamation-mark-do-before-the-function