TypeScript from Scratch in 2025: A Complete Guide for Beginners

Introduction to TypeScript: Where to Start in 2025

In 2025, TypeScript has firmly established itself as one of the most in-demand programming languages in the world of web development. If you're already familiar with JavaScript but want to write more reliable, scalable, and understandable code — TypeScript will become your indispensable tool. It's not just a "superset" of JavaScript, but a powerful type system that helps catch errors at the coding stage, rather than at runtime.

In this article, we'll break down where to start learning TypeScript in 2025: set up the environment, write your first code, and get acquainted with basic types and interfaces. You'll learn why large companies (Google, Microsoft, Airbnb) choose TypeScript and how it can simplify your life as a developer.

Why is TypeScript Relevant in 2025?

TypeScript is a strictly typed language that compiles to clean JavaScript. Its main advantage is static typing, which allows you to:

• Detect errors at compile time, rather than during code execution in the browser.
• Improve code readability: types act as documentation.
• Simplify refactoring: the IDE (e.g., VS Code) suggests all the places where code needs to be changed.
• Increase reliability of large projects and team development.

According to Stack Overflow surveys for 2024-2025, TypeScript is in the top 5 most loved and highest-paying languages. If you're planning a career as a frontend or backend developer (especially with Node.js), knowledge of TypeScript is a mandatory item on your resume.

Installing and Configuring TypeScript in 2025

Getting started with TypeScript is very simple. You'll need Node.js (version 18 or higher) and any code editor (we recommend Visual Studio Code with the official TypeScript extension).

Step 1: Install TypeScript globally

Open your terminal and run the command:

npm install -g typescript

Verify the installation:

tsc --version

You should see the TypeScript version (e.g., 5.5.0).

Step 2: Create your first TypeScript file

Create a file index.ts and write some simple code:

const greeting: string = "Hello, TypeScript!";const year: number = 2025;

function logMessage(message: string, year: number): void {    console.log(`${message} — Year ${year}.`);}

logMessage(greeting, year);

Step 3: Compile to JavaScript

Run the compiler:

tsc index.ts

After this, a file index.js will appear in the folder with clean JavaScript code, ready to run in the browser or Node.js.

Tip: For real projects, use tsconfig.json — a configuration file that sets compilation parameters. You can create it with the command:

tsc --init

TypeScript Type Basics

The main strength of TypeScript is its type system. Let's look at the basic types you'll use every day.

1. Primitive Types

TypeScript supports all JavaScript primitive types but adds annotations to them:

let name: string = "Anna";let age: number = 30;let isStudent: boolean = false;let notDefined: undefined = undefined;let empty: null = null;

2. Arrays and Tuples

Arrays can be declared in two ways:

let fruits: string[] = ["apple", "banana", "orange"];let numbers: Array<number> = [1, 2, 3];

Tuples are arrays of fixed length with known types:

let user: [string, number] = ["Anna", 30];