IIFE

• Stands for Immediately Invoke Function Invocation
• Can be use to minimize global variable declaration
• IIFE has the following syntax

(function () {})();

• IIFE is a function expression, not a function declaration
• We can not call a function declaration

function() {}()

This will throw syntax error.

But using IIFE we can call a function declaration immediately.

(function () {})();

Benefits of IIFE

• No global property is created, all the properties is inside the function declaration scope.

(function () {
  var a = 10;
})();

a;

Here a is defined inside the function expression, not available in the global scope.

• It creates it's own execution context, variable environment