Gain insights into JavaScript fundamentals. Delve into variables, operators, functions, arrays, objects, and loops. Discover essential concepts to advance further in your coding journey with this beginner-friendly course.

This is an introduction to JavaScript for the complete beginner. It'll provide the fundamentals of the language. Topics include variables, operators, functions, arrays, objects, and loops. After this course, you should be ready to further your learning through advanced courses or other resources.

There is NO installation required for this course. Code can be viewed and run directly from the lessons.

This course has been created by Arnav Aggarwal, a full-stack engineer. Arnav has attended a coding boot camp and has taught at another one. He has extensive experience understanding how people learn to code. In under a month, Arnav's published articles on JavaScript concepts have received over 50,000 views and have been featured on Medium.com and code mentor.io due to their value.

After this course, check out the next one in the series.

Step Up Your JS: A Comprehensive Guide to Intermediate JavaScript

https://goo.gl/GjM8Mu

Introduction to JavaScript: First Steps

There are two more variable types that we should discuss.

# `undefined`

`undefined` is meant to represent the idea that something doesn't exist. When we try to use a variable that has no value, we get `undefined`. Here's an example.

let variable;
console.log(variable); // -> undefined

When we declare a variable using `let` but don't give it a value, it receives the default value of `undefined`. This is JavaScript telling us that we're trying to use something that isn't there.

**`undefined` is a special variable type used to indicate that something is missing.** If we see it, it usually means something is wrong with our code.

For example, we'd have no reason to use a variable if we haven't given it a value, so when we do try to use it, JavaScript gives us `undefined`.

We can use it ourselves and assign the value to variables directly.

Learn two more variable types in JavaScript: null and undefined. Learn what they represent, how they differ, and how to use them.

Introduction

Variables

Operators & if-statements

Functions

Arrays

Objects

Loops

Conclusion

Null & Undefined

`undefined`