JavaScript in 2025: Where Should a Beginner Start? A Complete Guide

Introduction to JavaScript: Why It Matters in 2025

JavaScript (JS) remains one of the most in-demand programming languages in the world. In 2025, it is not just alive — it is thriving. Thanks to the Node.js platform, JavaScript has moved beyond the browser and become a universal tool for creating server applications, microservices, chatbots, and even desktop programs. If you want to start your journey in IT, JS is the ideal start. In this article, we will break down where to begin learning JavaScript in 2025, install Node.js, and write our first lines of code.

1. Installing and Setting Up the Environment (Node.js)

Before writing code, you need to prepare the environment. In 2025, the standard for running JS outside the browser is Node.js. This is a runtime environment that allows you to run scripts on a server or local computer.

How to Install Node.js

1. Go to the official website nodejs.org.
2. Download the LTS version (Long Term Support) — it is the most stable.
3. Run the installer and follow the instructions (it is recommended to leave all settings at default).
4. After installation, open a terminal (command line) and check the version:

node --versionnpm --version

If you see version numbers (e.g., v20.x.x), everything is working. npm is a package manager that you will need for installing libraries.

Creating Your First Project

Create a folder for the project and inside it a file index.js:

// index.jsconsole.log("Hello, JavaScript 2025 world!");

Run the script with the command:

node index.js

A message will appear in the terminal. Congratulations, you have just run your first code on Node.js!

2. Syntax Basics: Variables, Data Types, and Functions

JavaScript is a dynamically typed language. This means the type of a variable is determined automatically during execution. In 2025, the standard is ES2024, but the basic constructs remain the same.

Variables

Use let and const (avoid the outdated var):

const name = "Alexey"; // constant, value does not changelet age = 25;          // can be changedage = 26;              // ok// name = "Peter";     // Error! const cannot be reassigned

Data Types

• String: "text" or 'text'
• Number: 42, 3.14
• Boolean: true / false
• Array: [1, 2, 3]
• Object: { key: "value" }
• null and undefined

Functions

Modern syntax — arrow functions:

// Regular functionfunction greet(name) {    return `Hello, ${name}!`;}

// Arrow function (modern style)const greetArrow = (name) => `Hello, ${name}!`;

console.log(greetArrow("World")); // Hello, World!

Notice the backticks — these are template literals that allow you to insert variables directly into the text.

3. Practical Example: Console Calculator on Node.js

Now let's apply the knowledge in practice. Let's write a simple calculator that works in the terminal. For data input, we will use the built-in readline module.

// calc.jsconst readline = require('readline');

const rl = readline.createInterface({    input: process.stdin,    output: process.stdout});

console.log("Calculator on Node.js");console.log("Available operations: +,");