JavaScript Tutorial: Learn JavaScript from Scratch

Topics Covered

• An Introduction to JavaScript
• JavaScript Hello World
• JavaScript Arrays
• Array Filters 
• Array Reduce
• JavaScript Loops
• Javascript Functions
• JavaScript Closures
• JavaScript “This” Keyword
• JavaScript Form Validation
• JavaScript RegEx
• How to Validate an Email Address in JavaScript
• JavaScript Promises
• How to Implement JavaScript Async/Await
• JavaScript DOM Tutorial
• JavaScript Objects
• Javascript Games
• Build A Calculator App In JavaScript
• Javascript Projects: The Best Guide
• OOP in JavaScript
• JavaScript Learning Path
• JavaScript Interview Questions

JavaScript Tutorial: Table of Contents

Lesson 1: Introduction to JavaScript

JavaScript is an open-source programming language that allows users to create web-centric applications. Before you move on to the basics of JavaScript and the implementation of different functions, it is important to know what exactly JavaScript is and its uses. This lesson introduces you to the JavaScript programming language to create a foundation for the upcoming lessons.  

Lesson 2: JavaScript Hello World 

Now that you know what JavaScript is, it is time for you to try writing code using the programming language. This lesson takes you through a detailed step-by-step guide to writing code to print Hello World on your browser window. 

Lesson 3: Everything about JavaScript Arrays 

An array is a data structure in javascript that is used to store a list of values of the same data type. You will learn about array operations and methods in this JavaScript tutorial lesson. You will also learn about MapReduce and Filter.

Lesson 4: How to Use Array Filters in JavaScript

Array filters are used in JavaScript to filter out certain elements of an array based on the test condition specified by the programmer. To perform this, the filter goes through each element to check if it meets the test condition to filter them out accordingly. This lesson is all about array filter and how it works along with easy-to-understand examples that enable you to use them. Also included are the limitations of array filters in JavaScript and browsers that support array filters in JavaScript. 

Lesson 5: Everything about Array Reduce in JavaScript

The array reduce is a useful method in JavaScript that helps reduce an array to a single value. This lesson familiarizes you with array reduce, reducer and accumulator, properties of array reduce, and some examples that help you understand how they operate and how to use them. 

Lesson 6: Introduction to JavaScript Loops

Loops are programming constructs used to execute a set of code instructions repeatedly. In this lesson, the JavaScript tutorial, you will learn about the various iterative statements used in JavaScript, like do-while, for, and for-in loops.

Lesson 7: Everything about JavaScript Functions 

A JavaScript function helps programmers save time and effort by preventing them from writing the same code repeatedly. This reusable piece of code can be called from anywhere in the program when needed. This lesson of the JavaScript tutorial will help you learn all about JavaScript functions and their types—everything about the declaration, syntax, and working.

Lesson 8: Implementing JavaScript Closures 

A closure is a feature in JavaScript where an inner function has access to the outer function's variables. They help the programmer define the scope of functions and what isn’t. This lesson will teach you about closure, its properties, code examples, and variable scope. 

Lesson 9: All about JavaScript “This” Keyword 

This lesson of the JavaScript tutorial covers all of the basics you need to know about JavaScript “this” keyword, introduces the concept of reference, and finally acquaints you with the “this” keyword on a global and local scope.

Lesson 10: How to Implement JavaScript Form Validation

A web application is meant to be interactive and should be smart enough to validate the information stored by the end-user. And here’s where JavaScript Form Validation comes into play! Just like the name goes - form validation - checks and validates whether or not the provided information or data is accurate. Learn all about it in this lesson of the JavaScript tutorial.

Lesson 11: A Guide to JavaScript RegExs

Regular Expressions are a sequence of characters that combine to form a search pattern. This lesson will take you through JavaScript Regular Expressions, flags, patterns, quantifiers, metacharacters, examples, and a demo.

Lesson 12: How to Validate Email Address in JavaScript?

Validation in JavaScript is crucial to ensuring that only valid information is passed from the client side of the application to the server. This lesson will help you understand what validation is and how to validate an email address in JavaScript through detailed codes and the output. 

Lesson 13: JavaScript Promises and Ways to Implement Them

If a function keeps waiting for a resource to perform a network request, it might take more time, and while the function awaits the next step, the entire execution freezes. Asynchronous programming comes into play to solve this problem. With the ‘promise’ feature, you can perform and execute the next steps without changing or stretching the main execution thread. Know all about JavaScript Promises in this lesson of the JavaScript tutorial.

Lesson 14: How To Implement JavaScript Async/Await?

JavaScript is undoubtedly gaining popularity amongst web developers and in this lesson, you will learn its key feature, JavaScript async/await, which are asynchronous programming constructs. These are built on top of promises and generators to express asynchronous actions inline. In this JavaScript tutorial, Learn about synchronous programming, asynchronous programming, and JavaScript async functions. The list doesn’t end here: you will get demos for both JavaScript async and await.

Lesson 15: JavaScript DOM - 2020 Edition  

JavaScript accesses a webpage's contents, using the Document Object Model (DOM), which is created by the browser when a web page is rendered. Wondering what it would be like? The JavaScript tutorial is your answer to it! Learn all about DOM now.

Lesson 16: Everything You Need to Know About JavaScript Objects 

In this lesson of the Javascript tutorial, you will learn about objects, how to create one, their properties, methods, and accessors. Objects are an essential part of any Object-oriented programming language, so it is very important to learn the concept properly to prepare for real-world applications.

Lesson 17: An Introduction to JavaScript Games 

JavaScript is a lightweight and fast programming language compared to many others, which makes it a preferred option among programmers for developing games. This lesson is designed to teach you how to design two games - snake and tic-tac-toe in a step-by-step manner using the JavaScript programming language.

Lesson 18: A Guide to Building A Calculator App Using JavaScript 

JavaScript also allows you to build a calculator app; in this lesson, you will learn how to do so. The calculator app will be built using HTML, CSS, and JavaScript, assuming you know the basics of HTML and CSS. To build your calculator app, immediately start this lesson with a step-by-step guide.

Lesson 19: A Guide to JavaScript Projects

In addition to building a calculator app, JavaScript has many other practical applications - both simple and complex. In this lesson, you will learn some of the simpler practical applications of JavaScript, such as building to-do and weather applications, with a complete and easy-to-understand step-by-step guide.

Lesson 20: OOP in JavaScript and Ways to Implement It

Data is an important element of object-oriented programming (OOP), which protects data from accidental modifications from an outside function. Problems are broken down into objects, and the data and functions are built around them. This lesson will take you through the basics of OOP, its concepts, and related concepts, such as class implementation and encapsulation in JavaScript.

Lesson 21: A Guide to Understanding JavaScript Learning Path

JavaScript has various fundamental elements, such as variables, functions, control flow, and data types. Understanding these fundamental elements is crucial for implementing the programming language. This lesson aims to shed some light on both the fundamentals and advanced-level concepts of JavaScript and various JavaScript tools.

Lesson 22: JavaScript Versus .NET

Java is a popular programming language, and equally popular is .NET, a powerful framework owned by Microsoft. This lesson will acquaint you with Java and .NET by comparing them and helping you understand where to use the two.

Lesson 23: Common JavaScript Interview Questions 

Understanding all the JavaScript concepts is important when using the programming language. When you appear for a JavaScript interview, there are certain concepts that you should be thorough with to pass the interview. This lesson brings you the most common and important JavaScript interview questions for freshers and experienced candidates to help you have more clarity and prepare well. 

Lesson 24: How to Use Typeof in JavaScript

Typeof is an operator in javaScript that type-checks the data type and returns it to the operand passed to it. In JavaScript, you are not required to verify the variable type to declare them. The Typeof operator helps check the data type before its execution. In this lesson, you will learn about the different types of operands that can be checked with the help of Typeof and how to use Typeof with these operands with the help of some common use cases.

Lesson 25: JavaScript Coding Interview Tips and Tricks 

This lesson focuses on tips and tricks for JavaScript interviews based on the job descriptions. These tips will make it easier for you to clear coding interviews and familiarize you with certain aspects worth focusing on, such as details about the company, communication skills, and some practice questions for coding when appearing for an interview.

Lesson 26: All about JavaScript Callback Functions 

The JavaScript callback function is executed after the execution of another function is complete. It is executed in another function and is passed as an argument to that function. This lesson sheds some light on the importance of and types of callback functions, along with examples.

Lesson 27: JavaScript Events

An event is an action that occurs based on the instructions given by the user as input to give output. You will learn about types of JavaScript and some common event listeners in this lesson with the help of code snippets.

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Conclusion

This JavaScript tutorial can be the first step towards becoming a successful web developer. So, go through all the tutorial lessons aimed at building a strong foundation of JavaScript and get closer to a successful web development career!