undefined vs not defined in JS πŸ€” | Namaste JavaScript Ep. 6

Akshay Saini β€’ October 24, 2020
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Akshay Saini

@akshaymarch7

About

Namaste, I'm Akshay Saini, mentor and founder at Namaste Dev. I have worked as a Software Developer for big companies like Uber & Paytm. I've 10+ years of coding experience, and now I've left my job to pursue my passion for teaching full time. In this channel, you will find content for Interview preparation, Tech Tutorials, and my Tips and Tricks to advance with your career. You will find useful videos about Frontend Interview Tips, My Interview Experiences, and core concepts of Javascript. My videos have reached over 1.2M subscribers and I have trained over 100K students globally. If you are a frontend enthusiast, I welcome you to join our Tech community at Namastedev.com Hope this channel adds value to your frontend journey! Cheers, Akshay Saini Would love to connect with you, LinkedIn - https://www.linkedin.com/in/akshaymarch7 Instagram - https://www.instagram.com/akshaymarch7 Twitter - https://twitter.com/akshaymarch7 Facebook - https://www.facebook.com/akshaymarch7

Video Description

undefined is a special keyword in JavaScript and `undefined !== not defined`. JS is a loosely typed language (weakly typed language). This video covers an in-depth analysis of the undefined keyword and mistakes you should avoid while using this keyword. It is a special keyword in JS and it acts as a placeholder for variables until they are assigned any value in them. Understand the difference between undefined and not defined in JS. Many developers assume that undefined is exactly the same as not defined, but that's not true. undefined is a value in JavaScript and in fact, it also takes up memory space. So watch this video to understand everything in deep. My tech gear I use every day - http://google.peek.link/2pba Topics Covered: 00:00 - Introduction to undefined in JavaScript 00:29 - Code Example of undefined in JS 02:02 - Code Example of not defined in JS 04:33 - undefined vs not defined demo using code 07:46 - JS is a loosely typed language a.k.a weakly typed language 08:42 - Mistake you should not make while using undefined 10:17 - Teaser of next video - The Scope Chain 10:30 - Thank you for watching Namaste JavaScript πŸ™ Support this video series, NOT BY MONEY, but by sharing it with your friends. πŸ™ I'll give my best to come up with great content and everything absolutely for free on YouTube. 😊 If you are active on Social Media, please give a shoutout to Namaste JavaScript and help me reach more people. πŸ™ Cheers, Akshay Saini http://akshaysaini.in Would love to Stay Connected with you ❀️ LinkedIn - https://www.linkedin.com/in/akshaymarch7 Instagram - https://www.instagram.com/akshaymarch7 Twitter - https://twitter.com/akshaymarch7 Facebook - https://www.facebook.com/akshaymarch7 #NamasteJS #AkshaySaini

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