functionsfunctions in javascript

A function is a group of reusable code that can be called anywhere in your program. Functions eliminate the need of writing the same code again and again.

Functions also allow a programmer to divide a big program into a small and manageable chunks.

The way to define a function in Javascript is to use the “function” keyword.

function functionName() {
 //statements here ...

You could also use ES6 Arrow Functions as well

Passing Parameters

Parameters can be passed while calling a function. These type of functions are called Functions with parameters.


function greet(name, job){
document.write(`Name is ${name} and occupation is ${job}`);

<input type="button" onclick="greet('Lawson', 'Software developer')" value="greet" />

The Return Statement

A Javascript function can have an optional return statement. This is required if you want to return a value from a function. This statement should be the last statement in a function.


function add(a, b){
 return a + b;

console.log(add(2,3)) //5

Nested Functions

In a nested function, a function can be called inside another function. And it goes on and on depending on the logic of the program.


function showResult(){
console.log(add(2,3)) //Our function from the previous example

showResult() //5

Read more about recursive functions here

The End.

Leave a Reply

Your email address will not be published. Required fields are marked *