Forem: Athithya Sivasankarar

Types of Functions in JavaScript

Athithya Sivasankarar — Sat, 04 Apr 2026 16:58:52 +0000

1. Function Declaration

This is the basic way to create a function.

Example:

function sayHello() {
    console.log("Hello");
}

sayHello();

Output:

Hello

2. Function Expression

Here, the function is stored in a variable.

Example:

const sayHello = function() {
    console.log("Hello");
};

sayHello();

Output:

Hello

3. Arrow Function (Lambda)

Short and modern way to write functions.

Example:

const sayHello = () => {
    console.log("Hello");
};

sayHello();

Output:

Hello

4. Anonymous Function

Function without a name.

Example:

const greet = function() {
  return "Hi there!";
};

console.log(greet());

Output:

Hi there!

5. Callback Function

A function passed inside another function.

Example:

function greet(name, fun) {
    fun(name);
}

greet("Ram", function(name) {
    console.log("Hello " + name);
});

Output:

Hello Ram

6. IIFE (Immediately Invoked Function)

Runs immediately after writing.

Example:

(function() {
    console.log("Run now");
})();

Output:

Run now

7. Constructor Function

Used to create objects.

Example:

function Person(name) {
    this.name = name;
}

let p1 = new Person("Ram");
console.log(p1.name);

Output:

Ram

8. Generator Function

Used to return values one by one.

Example:

function* num() {
    yield 1;
}

let n = num();
console.log(n.next().value);

Output:

Reference

https://www.geeksforgeeks.org/javascript/functions-in-javascript/

Understanding Functions in JavaScript

Athithya Sivasankarar — Fri, 03 Apr 2026 17:42:02 +0000

What is a Function?

A function is a block of code designed to perform a specific task.
Instead of writing the same code again and again, you can write it once inside a function and reuse it whenever needed.

Why Use Functions?

Functions are useful because they:

Reduce code repetition
Make code easier to understand
Help in organizing large programs
Allow reuse of logic

How to Create a Function

In JavaScript, you can create a function using the function keyword.

Example:
function greet() { console.log("Hello, welcome to JavaScript!"); }
How to Call a Function

To execute (run) a function, you simply call it by its name.

greet();

Output:
Hello, welcome to JavaScript!

Functions with Parameters

Functions can take inputs called parameters.

Example:
function greetUser(name) { console.log("Hello " + name); } greetUser("Athithya");

Output:
Hello Athithya

Functions with Return Value

A function can return a value using the return keyword.

Example:
function add(a, b) { return a + b; } let result = add(5, 3); console.log(result);

Output:
8

Reference:

[https://developer.mozilla.org/en-US/docs/Web/JavaScript/Guide/Functions]

Student Marks Analysis Using JavaScript(Flow diagram)

Athithya Sivasankarar — Fri, 03 Apr 2026 05:46:45 +0000

Student Marks Analysis Using JavaScript (While Loop)

Athithya Sivasankarar — Thu, 02 Apr 2026 09:01:31 +0000

Program Explanation: Student Marks Analysis in JavaScript

This program is designed to analyze student marks using JavaScript. It calculates the total marks, average, number of failed subjects, and finally assigns a grade based on performance.

Step 1: Initialize Variables
let mark = [20,35,90,85,70];
let i = 0;
let failcount = 0;
let avg = 0;
let total = 0;
mark[] → Array storing marks of 5 subjects
i → Loop counter
failcount → Counts subjects where marks are less than 35
total → Stores sum of all marks
avg → Stores average marks

Step 2: Loop Through Marks
while(i < 5)
{
if(mark[i] < 35)
{
failcount++;
}
total = mark[i] + total;
i++;
}
The while loop runs from index 0 to 4
For each subject:
If marks are less than 35 → student failed in that subject
Add marks to total

Step 3: Display Total and Fail Count
console.log("fail count ->" + failcount);
console.log("Total ->" + total);
Prints number of failed subjects
Prints total marks

Step 4: Calculate Average
avg = Math.floor(total / 5);
console.log("Average ->" + avg);
Average is calculated by dividing total by number of subjects
Math.floor() removes decimal values (rounds down)

Step 5: Grade Calculation Logic
if(failcount > 0)
{
console.log("no grade");
}
If the student fails in any subject → No grade is assigned
If No Failures, Assign Grade:
else if(avg >= 90)
{
console.log("Grade A");
}
else if(avg >= 80)
{
console.log("Grade B");
}
else if(avg >= 70)
{
console.log("Grade C");
}
else if(avg >= 60)
{
console.log("Grade D");
}
else if(avg >= 50)
{
console.log("Grade E");
}
else
{
console.log("No Grade");
}
Grade is assigned based on average marks:
90+ → Grade A
80–89 → Grade B
70–79 → Grade C
60–69 → Grade D
50–59 → Grade E
Below 50 → No Grade

Final Output (For Given Input)
fail count -> 1

Total -> 300

Average -> 60

no grade

Program:

Output:
fail count ->0
Total ->357
Average ->71
Grade C

=== Code Execution Successful ===

Multiples of 3 and Multiples of 5 javascript program

Athithya Sivasankarar — Sat, 28 Mar 2026 09:22:06 +0000

Looping Programs – Flowcharts

Athithya Sivasankarar — Fri, 27 Mar 2026 08:47:07 +0000

Multiples of 3 AND 5 &
Multiples of 3 OR 5
Divisors of Given Number &
Count of Divisors

Count of Digits &
Sum of Digits

What is JavaScript? (A Beginner-Friendly Overview)

Athithya Sivasankarar — Thu, 26 Mar 2026 09:40:20 +0000

If you’ve ever clicked a button on a website and something magical happened—like a pop-up appearing, a form validating, or content updating without refreshing the page—you’ve already seen JavaScript in action.

But what exactly is JavaScript?

Let’s break it down in a simple and clear way.

The Language That Brings Websites to Life

At its core, JavaScript is a programming language that makes websites interactive.

Think of a website like a human body:

HTML is the skeleton (structure)
CSS is the skin and style (appearance)
JavaScript is the brain and muscles (behavior)

Without JavaScript, websites would just sit there—static and lifeless.

What Can JavaScript Do?

JavaScript is incredibly powerful. Here are some common things it can do:

Show popups and alerts
Validate forms (like checking email or password input)
Create animations and sliders
Update content without refreshing the page
Build full web applications

In fact, popular platforms like Netflix, Instagram, and YouTube rely heavily on JavaScript.

How Does It Work?

JavaScript runs directly in your browser—such as Chrome, Firefox, or Edge.

When you visit a website:

The browser loads HTML and CSS
Then it executes JavaScript
JavaScript responds to user actions (clicks, typing, scrolling)

This is what makes websites feel fast, responsive, and interactive.

A Simple Example

Here’s a basic JavaScript example:

alert("Hello, World!");

When this runs, your browser displays a popup saying "Hello, World!"

Simple, right? But this is just the beginning.

Why Should You Learn JavaScript?

If you’re getting into tech, JavaScript is one of the best skills you can learn:

Beginner-friendly
Used everywhere (frontend and backend)
High demand in the job market
Works with powerful frameworks like React and Node.js

Whether you want to build websites, apps, or even games—JavaScript is a great starting point.

JavaScript Is Everywhere

Today, JavaScript goes far beyond the browser:

Backend development (Node.js)
Mobile apps (React Native)
Desktop apps (Electron)
Even IoT devices

It has truly become a universal programming language.

Final Thoughts

JavaScript is not just a programming language—it’s what makes the web come alive.

If HTML builds the structure and CSS makes it beautiful, JavaScript adds intelligence and interaction.

So if you're starting your coding journey, learning JavaScript is one of the smartest moves you can make.

Thanks for reading!