TypeScript from Scratch in 2025: A Complete Guide for Beginners

Introduction to TypeScript: Where to Start in 2025

In 2025, TypeScript confidently holds the position of one of the most in-demand programming languages in web development. If you are already familiar with JavaScript and want to move to the next level, or are just starting your journey in programming — TypeScript will be your reliable foundation. In this article, we will break down where to start learning TypeScript in 2025, set up the development environment, and write our first programs.

TypeScript is a strictly typed superset of JavaScript, developed by Microsoft. It adds static typing, interfaces, generics, and many other modern features to the code, making development safer and more predictable.

Why Learn TypeScript Specifically in 2025?

TypeScript has become the de facto standard for large projects. Giants like Google, Microsoft, Airbnb, and many others actively use it in their products. Here are a few reasons why you should start right now:

• Ecosystem Stability — TypeScript version 5.x is a fully mature and reliable tool.
• High Market Demand — jobs for TypeScript developers are among the highest paying.
• Excellent Tool Support — VS Code, WebStorm, ESLint, Prettier work with TypeScript "out of the box".
• Smooth Learning Curve — if you know JavaScript, you already know 80% of TypeScript.

Step 1: Installation and Environment Setup

To work with TypeScript, you will need Node.js (version 18 or higher). Install it from the official website nodejs.org. After installation, check the version in the terminal:

node -vnpm -v

Now install TypeScript globally via npm:

npm install -g typescript

Verify the installation:

tsc -v

You should see a version number, for example Version 5.5.0. Congratulations, your environment is ready!

Step 2: First Program in TypeScript

Create a folder for the project and a file hello.ts:

mkdir my-first-tscd my-first-tstouch hello.ts

Open the file in an editor and write:

function greet(name: string): string {    return `Hello, ${name}! Welcome to the world of TypeScript 2025.`;}

const userName: string = "Alexey";console.log(greet(userName));

Notice the type annotations : string — this is a key difference from JavaScript. Now compile the code into JavaScript:

tsc hello.ts

A file hello.js will appear in the folder. Run it:

node hello.js

You will see: Hello, Alexey! Welcome to the world of TypeScript 2025.

Step 3: Typing Basics — Data Types and Interfaces

TypeScript offers a rich type system. Let's look at the basic types:

// Primitive typeslet isReady: boolean = true;let count: number = 42;let message: string = "TypeScript";

// Arrayslet numbers: number[] = [1, 2, 3];let names: Array<string> = ["Anna", "Ivan"];

// Tuplelet pair: [string, number] = ["age", 30];

// Enumenum Direction {    North,    East,    South,    West}let dir: Direction = Direction.North;

Interfaces are a powerful tool for describing the structure of objects:

interface User {    id: number;    name: string;    email: string;    isActive?: boolean; // optional property}

function createUser(user: User): void {    console.log(`User created: ${user.name} (${user.email})`);}

const newUser: User = {    id: 1,    name: "Maria",    email: "maria@example.com"};

createUser(