JavaScript Tutorial: Learn JavaScript from Scratch
  • Intermediate
  • 27 Lessons
  • 2 hrs of Learning
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Tutorial Highlights

  • JavaScript is a text-based programming language created by Netscape Communications. It is used on both server-side and client-side to build interactive web pages, applications, and games. 
  • With JavaScript, programmers can develop web pages that characterize dynamicity and are user-friendly to engage users. Being versatile and easy to learn, JavaScript is a preferred programming language among aspiring programmers. 
  • Our JavaScript tutorial takes learners through the fundamentals of JavaScript and its elements, such as arrays, loops, closure, Regex, and various other functions. Each lesson has various code examples to help you learn how to implement these concepts.

Skills Covered

  • Array
  • Function
  • Object
  • Promise
  • Regex
  • Closure
  • Dom
  • JavaScript for loop
  • Form Validation
  • JavaScript Games

Topics Covered

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

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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 which 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 that are used to execute a set of instructions of code repeatedly. In this lesson of 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 writing the same code again and again. 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.

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Lesson 8: Implementing JavaScript Closures 

A closure is a feature in JavaScript where an inner function has access to the variables of the outer function. They help the programmer define what is the scope of functions and what isn’t. In this lesson, you will learn 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, and also 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 or not. 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, and quantifiers, metacharacters, along with examples and a demo. 

Lesson 12: How to Validate Email Address in JavaScript?

Validation in JavaScript has a crucial role to play to ensure 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 along with the output. 

Lesson 13: JavaScript Promises and Ways to Implement Them

If a function keeps waiting for a resource for performing a network request, it might take more time, and while the function awaits the next step, the entire execution freezes. In order to solve this problem, asynchronous programming comes into play. 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, that is, JavaScript async/await, which are asynchronous programming constructs. These are built on top of promises and generators to express asynchronous actions inline. To learn all about synchronous programming, asynchronous programming, and JavaScript async functions in this JavaScript tutorial. The list doesn’t end here: you will get demos for both JavaScript async and await.

Lesson 15: JavaScript DOM - 2020 Edition  

JavaScript accesses the contents of a webpage making use of 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, which makes it very important to learn the concept properly, making you ready for real-world applications.

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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, and in this lesson, you will learn how. The calculator app will be built using HTML, CSS, and JavaScript, assuming you know the basics of HTML and CSS. To build your own calculator app, start this lesson with a step-by-step guide right away.  

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 be learning some of the simpler practical applications of the JavaScript programming language, such as building a to-do application and weather application 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 keeps the data protected 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 other 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, among others. An understanding of these fundamental elements in JavaScript is crucial for the implementation of the programming language. This lesson aims to shed some light on both 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 that is owned by Microsoft. This lesson will acquaint you with Java and .NET by drawing a comparison between them and help you understand where to use the two. 

Lesson 23: Common JavaScript Interview Questions 

Understanding all the JavaScript concepts is important to put the programming language to use. When you appear for a JavaScript interview, there are certain concepts that you should be thorough with to be able to pass the interview. This lesson brings you the most common and important JavaScript interview questions for freshers as well as 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. 

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

About the Author


Simplilearn is one of the world’s leading providers of online training for Digital Marketing, Cloud Computing, Project Management, Data Science, IT, Software Development, and many other emerging technologies.

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