Adding functions in javascript

docs/languages/javascript/ex-8.md

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+---
+id: functions-in-javascript
+sidebar_position: 8
+title: Functions in JavaScript
+sidebar_label: Functions in JS
+---
+
+A function in JavaScript is similar to a procedure—a set of statements that performs a task or calculates a value, but for a procedure to qualify as a function, it should take some input and return an output where there is some obvious relationship between the input and the output.
+
+<AdsComponent />
+
+## **Functions Declaration**
+
+Function Declarations also known as function statement or function definition consists of function keyword, function name, parameters separated by commas and function body enclosed by curly braces ```{ /*function body*/ }```
+
+
+```javascript
+function printName(name) {
+    return name;
+}
+```
+
+In the example above, the function ```printName``` takes one parameter called ```name```. The function body consist of one statement that returns the name.
+
+<Ads />
+
+## **Function Expressions**
+
+Function expressions are a way to define a function as part of an expression. Unlike function declarations, which define a function with a name, function expressions can be anonymous (without a name) or named. 
+
+## 1. **Anonymous Function Expression**
+An anonymous function expression is a function that doesn't have a name. It can be assigned to a variable, passed as an argument to another function, or returned from another function.
+
+```javascript
+const greet = function() {
+    console.log("Hello!");
+};
+
+greet();
+```
+
+## 2. **Named Function Expression**
+A named function expression includes a name. This can be useful for recursion or for better debugging.
+
+```javascript
+const greet = function sayHello() {
+    console.log("Hello!");
+};
+
+greet();
+```
+
+## 3. **IIFE (Immediately Invoked Function Expression)**
+An IIFE is a function that runs as soon as it is defined. It’s often used to create a local scope.
+
+```javascript
+(function() {
+    console.log("This runs immediately!");
+})();
+```
+
+<AdsComponent />
+
+## **Function Call**
+
+Calling a function means executing the code defined within it. There are various ways to call a function.
+
+```javascript
+const greet = function(name) {
+    console.log("Hello ", name);
+};
+
+greet("World!"); //Output: Hello World!
+```
+
+The above example is calling a function with argument
+
+
+```javascript
+const obj = {
+    greet: function() {
+        console.log("Hello from an object!");
+    }
+};
+
+obj.greet(); // Output: Hello from an object!
+```
+
+The above example is calling a method of an object
+
+```javascript
+const multiply = (x, y) => x * y;
+
+console.log(multiply(2, 3)); // Output: 6
+```
+
+The above example is of calling an arrow function
+
+
+## More Resources:
+
+- [MDN Web Docs: Functions](https://developer.mozilla.org/en-US/docs/Web/JavaScript/Guide/Functions)
+- [W3Schools: JavaScript Functions](https://www.w3schools.com/js/js_functions.asp)