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Introduction To JavaScript

*Who is this course for? *
This course is for developers of every level, from beginner to advanced, who want to improve their JavaScript skills and get up to date with all the upgrades done to the language specification since 2015

What is Javascript?
Javascript is a lightweight, interpreted, or just-in-time compiled programming language with first-class functions. JavaScript was developed by Brendan Eich in 1995.

What can Javascript do?

  • JavaScript Can Change HTML Content
  • Can Change HTML Attribute Values
  • Change HTML Styles (CSS)
  • JavaScript Can Hide HTML Elements
  • Show HTML Elements

How does JavaScript work?
JavaScript can be added to a page’s code using tags with the type attribute text/javascript or as a header file with the extension .js. A web browser then downloads and runs the script, changing it into the dynamic objects and effects seen on a screen.<br> JS framework<br> ReactJS, Angular, Vue.js and Bootstrap.</p> <p><strong>How it is used</strong></p> <ul> <li>Build web and mobile applications</li> <li>Add interactive elements to a website</li> <li>Many developers use JavaScript to make web pages more interactive</li> <li>Develop games</li> <li>The programming language</li> <li>Build efficient IoT systems</li> </ul> <p><strong>How to Run JavaScript?</strong><br> JavaScript cannot run on its own. When a user requests an HTML page with JavaScript in it, the script is sent to the browser and it is up to the browser to execute it. <br> To start with, you need a text editor to write your code and a browser to display the web pages you develop. You can use a text editor of your choice including Notepad++, Visual Studio Code, Sublime Text, Atom or any other text editor you are comfortable with. You can use any web browser including Google Chrome, Firefox, Microsoft Edge, Internet Explorer</p> <p><strong>Main uses are:</strong></p> <ul> <li>Client-side validation,</li> <li>Dynamic drop-down menus,</li> <li>Displaying date and time,</li> <li>Displaying pop-up windows and dialog boxes (like an alert dialog box, confirm dialog box and prompt dialog box),</li> <li>Displaying clocks etc.</li> </ul> <p><strong>JavaScript Example</strong></p> <script> document.write("Hello JavaScript by JavaScript");

*Javascript frameworks and libraries available:


  • jQuery
  • Vue.js
  • Ext.js
  • Ember.js
  • Meteor
  • Mithril
  • Node.js
  • Polymer
  • Aurelia
  • Backbone.js `

Top comments (0)

This post blew up on DEV in 2020:

js visualized

🚀⚙️ JavaScript Visualized: the JavaScript Engine

As JavaScript devs, we usually don't have to deal with compilers ourselves. However, it's definitely good to know the basics of the JavaScript engine and see how it handles our human-friendly JS code, and turns it into something machines understand! 🥳

Happy coding!