What should i learn before javascript

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Table of Contents
Introduction
Advantages of JavaScript
Job Prospects
Prerequisites
Online Javascript IDE:
How To Learn JavaScript
Javascript Tutorials:
Free Resources:
Official Documentation:
Javascript Projects
Certification
Interview Questions
How To Learn JavaScript Summary
What should I learn first before learning JavaScript?
How do I start learning JavaScript?

Introduction

JavaScript is a free scripting language that works on client-side as well as server-side. It is text-based and works along-side HTML and CSS to enhance code functionality and add interactive elements. In short, JS can bring life to otherwise boring and static web pages. JS is interpreted, which means the code need not be compiled. For huge projects that use a lot of interactive content, separate JavaScript files with the extension .js are created. However, JS can also be embedded in HTML code using <script> tag. Some common use-cases of JS are interactive maps, live news updates, form validations, creating landing pages, etc.

A simple JS program is as follows:

<!DOCTYPE html>
<html>
<body>
<h2>JavaScript Example</h2>
<p id="demo">I will change once you Click! the button...</p>
<button type="button" onclick='document.getElementById("demo").innerHTML = "Hello Beautiful!"'>Click!</button>
</body>
</html>

In this code, the text is changed on click of the button ‘Click!’ due to the onClick JavaScript event!

Advantages of JavaScript

JavaScript completely changed the way the world looked at browsers. It gave the ability to build complex websites and make the whole business process digital! Some advantages of JavaScript are:

High performance: JS is lightweight & fast as it can be immediately run on the browser (client machine)
Simple and popular: We have been using it for ages, and it hasn’t lost the hold!
Interoperable: can be used with a variety of other languages and applications
Reduces server load as it works on the client-side
Makes pages lively, dynamic, and rich
It comes with many free tools to enhance functionality
The functionality of JS can be extended to the backend using Node.js

Job Prospects

JavaScript stands firm, and why not; web applications are the present and the future of this changing digital world. New websites are added every single day with loads of interactive elements, which means there will always be work for JavaScript developers. That is why it is one of the Top 5 programming languages of 2020. There are about 24000 job openings for JS developers, and on average, they are paid about $118k per year.

Prerequisites

To learn JavaScript, you must know the basics of HTML and CSS, both of which are extremely easy to learn. For a working knowledge of JavaScript and most web-based projects, this knowledge will be sufficient. For more advanced projects and skills, it is recommended to know basic OOP concepts and an OOP based programming language (like Java).

You can install an IDE or use code editors, or even use notepad or Textpad to write JS code. IDEs and editors provide intuitive programming experience and faster results than programming with editors like notepad, where you have to type everything from scratch.

IDE

Although you can type and run a JS program with a notepad, an IDE makes it easy to debug the code and provide support to ALM (Application Lifecycle Management) systems. Here are the top 3 IDEs/source-code editors:

WebStorm: WebStorm provides smart assistance and code completion, refactoring for CSS, TypeScript, JS. You can test your functionality and troubleshoot with the built-in debugger that targets both Node.js and client-side code. Use the 30-day trial version to get the feel of the product before you go for buying it.
Visual Studio Code: There is literally no language that VS Code doesn’t support. It is a free, developer-friendly cross-platform IDE that offers features like built-in Git integration, smart code completion, code debugging from the editor itself, and much more. It is highly extensible.
Atom: Atom is a highly popular IDE from GitHub. It provides smart context-based code completion, easy code navigation, a full set of diagnostic tools to understand and debug code, and many more features. It is free and open-source, and you can add some fun to your coding using the pre-installed themes and styles.

Online Javascript IDE:

AWS Cloud9: Apart from JS, AWS Cloud9 also supports development for C, C++, Perl, Python, Node.js, etc. It is entirely written in JS, and the backend is in Node.js. It is an online open-source IDE, and one needs an AWS account to get access. Some features are syntax highlighting, support for npm and basic UNIX commands, simultaneous editing, real-time language analysis, and customizable key bindings.

How To Learn JavaScript

Many free and paid courses and tutorials are available to learn JavaScript. For in-depth knowledge, you can also purchase a few good books like A Smarter Way to Learn JavaScript and Effective JavaScript: 68 Specific Ways to Harness the Power of JavaScript. However, to start working on projects, you need only a little theory and more hands-on, so we recommend you to take up tutorials and short courses that will get you onboard quickly.

Below are the top 5 JavaScript tutorials:

Javascript Tutorials:

The Complete JavaScript Course 2020: Build Real Projects!: An introductory course that also covers some expert-level topics starts with JS fundamentals like variables, loops, control statements, and modern OOPS and goes on to explain the modern tools like Parcel, NPM, Babel, and ES6 modules. You will also learn about closures, higher-order functions, and other complex topics. The course is reasonably priced and offers 74 hours of on-demand video and lifetime access to the material.
Front-end web developer: Nanodegree: This is a paid course of 4 months, which covers some advanced topics like Web API, asynchronous applications, etc. You should have fundamental knowledge of HTML, CSS, JavaScript to take up this course. You will get to do real-world projects with proper feedback and mentoring.
Fullstack Javascript: If you want to be a full-stack JS developer, this is the right course for you. The course teaches JS from scratch. Once you are thorough with basics, you will also learn about AJAX, Asynchronous programming, Fetch API, Node.js, and the various ways to write JS applications outside the browser (like from command-line). Database concepts from SQL basics to using SQL ORMs with Node.js and building a simple CRUD application are also taught.
Introduction to JavaScript | FreeCodeCamp: You can begin your learning curve through this free course, starting from scratch. It is well-paced and covers even the minute concepts that other courses will easily ignore. It follows a hands-on approach and covers lots of examples for developers to work on. This tutorial is an excellent example of learning by doing.
The JavaScript Tutorial (javascript.info): Try this well-structured free tutorial that starts from scratch, right from setting up code editors, manuals and developer console, JS fundamentals, debugging, transpilers, and object-oriented concepts like ‘this’, references, ‘new’ operator, etc. to functions, stack, recursions, inheritance, prototype, and many more advanced concepts. The author provides simple examples to demonstrate each topic making learning easy for newbies.

Free Resources:

Apart from the paid and free tutorials mentioned above, here are some more free video and blog links that will get you started:

Mozilla Developer Network JavaScript Guide
JavaScript Tutorial for Beginners (youtube.com)
JavaScript crash course in 8 hours

Official Documentation:

To learn more about JavaScript built-in values, properties, functions, etc., visit the developer reference page for JavaScript.

Javascript Projects

It is straightforward to start doing JavaScript projects as no set up is required. From building a simple calculator to a complex ball bouncing game, options are plenty. You can start with our list of JavaScript projects for beginners to get the knack of it. You can then go for more projects like animation design, classroom management systems (you may need node.js for this), web assistants that help in scraping and summarizing website content, memory game, a game of Tetris, etc.

Certification

Certifications will help you boost confidence and apply for jobs that are more challenging and fruitful. You will also get an advantage over other candidates with the same skills and experience if you have certifications in hand. Our pick of Best JavaScript Certification will help you get result-oriented, practical skill sets, and knowledge. Most of the certifications are for beginners and start with general programming principles before moving on to more advanced topics like form validation, animation, communication with the database, etc.

Interview Questions

Now that you are confident enough, you should go for that dream interview. To prepare yourself well, check Hackr.io’s comprehensive list of JavaScript interview questions asked in almost all the interviews. Some important questions are:

How is JavaScript different from Java?
Difference between attributes and property?
Can you differentiate between let and var?
Explain the difference between function declaration and function expression?
In how many ways can you create an array in JS?
Please explain Self Invoking Function and its syntax.
Write a code to demonstrate how to get the inner HTML of an element in JavaScript.
How can you import all exports of a file as an object in JavaScript?
Could you explain escape() and unescape() functions?
What are the various ways of embedding JavaScript code in an HTML file?

For the complete set, check the JavaScript Interview Questions page.

How To Learn JavaScript Summary

JavaScript is the king of web applications, and you have to keep practicing and be ready to face new challenges. There might be days when you won’t understand the exact issue and have to debug a lot, but eventually, you will get there. Any UI-based programming language, for that matter, requires patience and consistent practice.

JS is used for client as well as server-side programming and is an interpreted language, which means no additional compiler is required

You can simply type JS code inside any HTML file using the <script> tag and make it work by opening it in a browser

To learn JS, you should also learn HTML and CSS

JavaScript uses the DOM API to manipulate the HTML and CSS on a web page
Learn through courses, tutorials, projects, and then take up certifications to test your knowledge and learn industry-level skills too.

Interview questions will help you understand the latest industry requirements
Practice is the key to learning JS

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Best Javascript Courses
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What should I learn first before learning JavaScript?

Prerequisites. To learn JavaScript, you must know the basics of HTML and CSS, both of which are extremely easy to learn. For a working knowledge of JavaScript and most web-based projects, this knowledge will be sufficient.