Creating a closure is nothing more than accessing a variable outside of a function's scope. Please note that a function inside a function isn't a closure. Closures are always use when need to access the variables outside the function scope.

Closures mechanism is used to enable the data privacy.

Why is closures important?

• Closures provide a way to associate data with a method that operates on that data.
• They enable private variables in a global world.
• Many patterns, including the fairly popular module pattern, rely on closures to work correctly.
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