Exploring How JavaScript Change Image src | 3 Methods
In this article, we’ll explore three methods to change image src using JavaScript. From directly manipulating the src property to using the HTML DOM, we’ll equip you with the knowledge …
JavaScript Tutorial 2026: Free ES6+ Beginner to Advanced
JavaScript is the only language that runs natively in every web browser, making it essential for any web-based BSIT capstone, modern web application, or interactive site. This hub collects free JavaScript tutorials from basic variables and functions through modern ES6+ features, DOM manipulation, async programming, and integration with REST APIs.
What you’ll learn in the JavaScript tutorial series
Core fundamentals: variables (let/const), data types, operators, conditionals, loops
Functions: declarations, expressions, arrow functions, closures, callbacks
DOM manipulation: selecting elements, modifying content, event handling
ES6+ features: destructuring, spread/rest, template literals, modules
Async programming: Promises, async/await, fetch API, error handling
Array methods: map, filter, reduce, find, forEach (functional programming patterns)
Object-Oriented JavaScript: classes, prototypes, inheritance, getters/setters
Modern tooling: npm, webpack/Vite, ESLint, Prettier
Why every BSIT student should know JavaScript
JavaScript is unavoidable in modern web development, it’s the only language browsers natively execute. Even capstones built on PHP + MySQL back-ends need JavaScript for client-side validation, AJAX form submissions, dynamic UI updates, and modern interactive features. Beyond browsers, Node.js lets you write server-side JavaScript too, opening up the entire MEAN/MERN/MEVN stack family.
JavaScript vs TypeScript: which should I learn?
Start with JavaScript first to understand the core language. Once you’re comfortable, TypeScript is a superset that adds optional static typing, it catches more bugs at compile time and is the modern standard for large React/Vue/Angular projects in 2026. Most BSIT capstones can use either; pick TypeScript if your panel values type safety and modern best practices.
Related JavaScript resources
JavaScript Projects, 55+ downloadable JS capstones
React Projects, JS framework for modern UIs
Vue.js Projects, alternative front-end framework
Node.js Projects, server-side JavaScript
TypeScript Tutorial, add types to your JS
AJAX Projects, async API patterns
Scroll down to browse the full JavaScript tutorial catalog ↓
How to Get Timezone in JavaScript
It is important for web developers to accurately define and display the timezone of users. In this article, we will discuss the different techniques and methods on how to get …
What is the “e” in JavaScript functions and why is it important?
You don’t understand what is the meaning of “e” parameter inside a JavaScript function? Keep on reading! This article will acquire a thorough understanding of this vital component of parameter …
How to Count Consonants in a String in JavaScript?
You need to analyze code and count consonants in a string using JavaScript, but you don’t know how? Well, don’t worry! It is because we will guide you on how to …
How to Move Item in Array JavaScript?
When it comes to functioning with arrays in JavaScript, it’s important to understand how to manage the data stored for them adequately and How to Move Item in Array JavaScript. …
What is the used of colon (:) in JavaScript?
In this article, we will explore how the colon (:) is used in JavaScript and how it helps make the language more powerful and flexible. This flexible symbol functions as …
How to Reverse a String in JavaScript
When it comes to running strings in JavaScript, one of the simple tasks is reversing a string. Either you’re a beginner learning JavaScript or a professional developer looking for different …
How to add leading and trailing zeros 00 to a number in JavaScript?
Are you wondering how to add leading and trailing zeros 00 to a number in JavaScript? Well, keep on reading! Discover how to format numbers in JavaScript with leading zeros. …
How to print in JavaScript
One of the common functions in web development is printing content directly from a web page. In this article, you will have to learn the different methods on how to …
How to Set Default Selected Value in Dropdown Using JavaScript
One of the common requirement is setting a default selected value in a dropdown menu. In this article, we will discuss the different techniques and methods to complete this using …
How to generate unique ID for each array of objects in JavaScript?
In this article, we will explore several methods on how to generate unique IDs for each array of objects in JavaScript. Apart from that, we’ll provide you with practical solutions for …
How to combine html CSS and JavaScript in one file
In current web development, combining HTML, CSS, and JavaScript in a single file has turned into a popular method. This method provides multiple benefits, including enhanced performance, decrease HTTP requests …
Frequently Asked Questions
Do I need to learn JavaScript before React or Vue?
Yes, solid JavaScript fundamentals are essential before tackling frameworks. Spend at least 4-8 weeks on core JS (variables, functions, arrays, objects, DOM, async) before touching React, Vue, or Angular. Jumping straight to a framework without knowing the underlying language leads to copy-paste developers who can't debug or extend their code, panels notice this in defense. ES6+ syntax (arrow functions, destructuring, spread/rest) is mandatory before frameworks.
What's the difference between var, let, and const?
var is the old (pre-2015) way to declare variables, function-scoped, hoisted, can be redeclared. Avoid in modern code. let is block-scoped, can be reassigned, can't be redeclared in the same scope. Use for variables whose value will change. const is block-scoped, can't be reassigned. Use by default; switch to let only when reassignment is needed. Rule of thumb: const by default, let when needed, never var.
What's async/await and why does it matter?
async and await are modern JavaScript syntax for working with Promises (asynchronous operations like fetching data from an API). Old callback-based code becomes deeply nested ("callback hell"). Promises improved this. async/await makes asynchronous code read like synchronous code, much easier to follow. Essential for any modern web app that talks to a server: const response = await fetch('/api/users'); const data = await response.json();.How do I run JavaScript outside a browser?
Install Node.js (free, cross-platform from nodejs.org), it's a JavaScript runtime that lets you execute .js files from your terminal. Use cases beyond browsers: server-side web apps (Express, Fastify, NestJS), command-line tools, build tooling (webpack, Vite), desktop apps (Electron), testing scripts (Jest, Playwright). Browse our Node.js Projects for server-side examples.
Should I learn TypeScript instead of JavaScript?
Learn JavaScript first, then add TypeScript when you're comfortable. TypeScript is JavaScript with optional static typing, it catches more bugs at compile time but adds complexity. For 2026 capstones using React/Vue/Angular, TypeScript is increasingly the standard. For pure jQuery or vanilla JS capstones, TypeScript is overkill. See our TypeScript Tutorial when you're ready.
What can I build with JavaScript for my capstone?
Browser-only capstones: games (Tic-Tac-Toe, Hangman, Memory, Flappy Bird), calculators and converters, interactive dashboards with Chart.js. Front-end + back-end (full-stack): MERN stack capstones (React + Express + MongoDB), real-time chat apps with Socket.io, e-commerce front-ends consuming a PHP back-end. Browse our JavaScript Projects for examples.