Closure in JavaScript

Closure is when a function remembers its lexical scope even when the function is executed outside its lexical scope.

We can make private variable with closure.

For Example

	function myFunction() {
	name = "Deepak";
	function displayName() {
	console.log(name);
	}
	show(displayName);
	}
	function show(displayName) {
	displayName(); // "Deepak"
	}
	myFunction();

view raw gistfile1.js hosted with ❤ by GitHub

	function myFunction() {
	name = "Deepak";
	return function() {
	console.log(name);
	};
	}
	function show() {
	myFunction()(); // "Deepak"
	}
	show();

view raw gistfile1.js hosted with ❤ by GitHub

	var add = (function() {
	var count = 0; // private variable
	return function() { // public anonymous function
	count += 1;
	console.log(count);
	};
	})();
	add(); // 1
	add(); // 2
	add(); // 3

view raw gistfile1.js hosted with ❤ by GitHub

	var name = (function() {
	var name = "Deepak"; // private variable
	return { // public API
	getName: function() {
	return name;
	},
	setName: function(newName) {
	name = newName;
	}
	};
	})();
	console.log(name.getName()); // "Deepak"
	name.setName("Chetan");
	console.log(name.getName()); // "Chetan"

view raw gistfile1.js hosted with ❤ by GitHub

Link 1 - Closure
Link 2 - Closure
Link 3 - Closure
Link 4 - Closure