Introduction to TypeScript
Welcome to the world of TypeScript!
If you are already familiar with JavaScript, then you are in the right place. TypeScript is built on top of JavaScript, which means everything you know about JavaScript still applies. But TypeScript adds more features that make it easier to write safe, reliable, and easier-to-maintain code.
What is TypeScript?
TypeScript is a programming language that is a superset of JavaScript. This means that TypeScript includes everything in JavaScript, but it also has extra features. The most important feature TypeScript offers is type checking.
In JavaScript, you don’t have to tell the computer what kind of data you are working with. For example, you can write code like this:
let message = "Hello, world!";
message = 42; // This works, but it might be a mistake!
In the code above, JavaScript doesn’t stop you from changing message from a string ("Hello, world!") to a number (42). This can cause bugs that are hard to find. But TypeScript solves this problem by adding types to your code.
Why Use TypeScript?
There are several reasons why developers choose TypeScript:
Safety: TypeScript helps find mistakes in your code before you run it. By checking the types, it makes sure you don’t accidentally use the wrong kind of data in the wrong place.
Better Tools: When you use TypeScript, your code editor can help you more. It can give suggestions, highlight errors, and show you where things go wrong while you write your code.
Easier to Maintain: As your code grows, it becomes harder to manage. TypeScript makes your code easier to understand and safer to change in the future.
TypeScript was created by Microsoft in 2012 and continues to be actively maintained and developed. Over the years, it has become the de facto standard in modern web development, so much so that proficiency in TypeScript is now often considered a requirement for many jobs in the field.
How Does TypeScript Work?
TypeScript code is written using types and then turned into regular JavaScript. The process of turning TypeScript into JavaScript is called compiling. The TypeScript compiler checks your code for errors and then creates a new file that is plain JavaScript.
This means that TypeScript works in any project that uses JavaScript. You can use TypeScript alongside your existing JavaScript code.
TypeScript makes writing code safer, cleaner, and more manageable. By checking for errors early and helping with better tools, it saves time and helps avoid mistakes. In this book, we will explore all the features TypeScript offers and learn how to use them to build better applications.
Let’s dive in immediately!