Gain insights into TypeScript's core concepts, from basics to advanced type checking and iterators. Learn about static typing and JS library support through practical, hands-on experience.

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If you’re looking to move beyond vanilla JavaScript and take your skills to the next level, then you’ve come to the right place. TypeScript is an in-demand language that sits on top of JavaScript. This means you can do everything you can in JavaScript with TypeScript, but also enjoy countless other perks including support for JS libraries, NPM, static typing, and much more.

In this course, you’ll start from the beginning and work your way up to more advanced concepts like type checking, iterators, and manipulating objects and arrays. You'll get a chance to get your hands dirty with plenty of real practice along the way.

For JavaScript developers, TypeScript is a must-know language, not only for today but also for years to come. Don't miss out.

Learn TypeScript: The Complete Course for Beginners

# Bang operator role
The bang operator is the use of the exclamation point symbol `!`. The operator can be used after a variable and before the dot to access a member. 

It is officially called the "non-null assertion operator". A variable with the value `undefined` or `null` can benefit from using the **bang operator** because it tells TypeScript that you know that even if the value can theoretically be `null` or `undefined`, it’s not possible for that particular usage. In a situation where the value cannot be `undefined`, instead of comparing against `null` or `undefined`, you could use the bang operator to access the value. 

# Caveat
It is important to understand that it can open the door to runtime error and a bang operator is not something you will often see in a project. Under the hood, TypeScript removes from the type of the variable, the union with `null` and `undefined`.

> Note: the code below throws an error


In this lesson, you will see how the bang operator is used in TypeScript.


Introduction

The Basics of Variables

Comment

Enum

Generic Type

Functions

Mapped Type

Objects

Index Signature

Variables Advanced

Exception

Alias

Type Checking

Iterators

Manipulating Objects and Array

Sharing Code

Conclusion

The Bang Operator

Bang operator role