TypeScript is a typed superset of JavaScript that compiles to plain JavaScript. In this post, we'll introduce you to TypeScript and its key features.

What is TypeScript?

TypeScript adds optional static typing, classes, and modules to JavaScript, making it easier to develop and maintain large-scale applications.

Key Features of TypeScript

Static typing
Object-oriented programming with classes
Improved tooling and IDE support
ECMAScript features from future versions

Basic Types in TypeScript

TypeScript includes several basic types:


let isDone: boolean = false;
let decimal: number = 6;
let color: string = "blue";
let list: number[] = [1, 2, 3];
let x: [string, number] = ["hello", 10]; // Tuple
enum Color {Red, Green, Blue}
let c: Color = Color.Green;

Interfaces

Interfaces are a powerful way to define contracts within your code:


interface Person {
  firstName: string;
  lastName: string;
}

function greeter(person: Person) {
  return "Hello, " + person.firstName + " " + person.lastName;
}

let user = { firstName: "Jane", lastName: "User" };
console.log(greeter(user));

Classes

TypeScript supports object-oriented programming with classes:


class Greeter {
  greeting: string;
  constructor(message: string) {
    this.greeting = message;
  }
  greet() {
    return "Hello, " + this.greeting;
  }
}

let greeter = new Greeter("world");

Conclusion

TypeScript offers many benefits for JavaScript developers, including better tooling, clearer code intent, and fewer runtime errors. As you continue to explore TypeScript, you'll discover how it can significantly improve your development workflow and code quality.