Dos and Donts: Best Practices When Learning JavaScript

With every programming language, there's a list of best practices; do's and don'ts. JavaScript is no exception. Some of these best practices are there for your protection (like always always always using semi-colons!), some to make your code more readable and less error-prone, and some to increase the efficiency of your code.

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[Tubeatorium]

The narrator is sooo professional and then, at 8:23, with a barely detectable break in her demeanor:  "... something called Automatic Semi-Colon Insertion.  It sounds complicated and perhaps a little painful..."  I love that she did that :)  Very funny  

[meruzhansargsyan]

Here is a tip for people watching in 2020 or later: never use var, use const and let to declare variables. Also put the statement “use strict”; at the top of your code. This makes sure that your code is as modern as possible

[victornaut]

Some of these are applicable not only to JS, but to any programming language.

[NoahNobody]

Some really nice tips. Thanks for the teaser.

[IsaacAsante]

Impressed by this insightful video. I'm subscribing now!

[jessupboyus]

write code for humans not computers. Don't Repeat Yourself. Keep it Simple.

[bustnoutloadedcaliber]

great video  o'reilly , its better then other videos i saw  :)

[StewartLynch]

I think that there is an error in that first example of choosing good variable names.
This will cast all values of the object as 0
Should the line theArray[i] = 0 not be
theArray[i] = obj[key];

[tolich]

Shouldn't message be set to div.innerHTML instead of empty string? What if we supposed to process more than one array?

[ReinardDolleschel]

Useful intro and appreciate the clear voice, but drop the silly stock pictures. "You can't have two variable names with the same names." might want to word that better.

[odunladeoluwaseun]

I went through everything on JavaScript at 3wschools, I can use all of them individually but still can't build any meaningful app. I can change contents on DOM, change styles, change image SRC but that is where it ends. where can I learn advance stuffs, like building a real life app

[dayvie]

Best practices for JavaScript: use let and const instead of var if you can.

[chubbyBunny]

What consoles should I download to practise on my PC?

[practicerepeat]

I tried this and does not work inside my body:

 <script>
      function arrayFromObject (obj) {
     var theArray = [];
 var i = 0;
 for (var key in obj) {
    theArray[i] = 0;
i++;
 }
 return theArray;
  }
  </script>

[x]

This is excellent marketing, might I say!

[glialcell]

Most of these aren't exclusive to Javascript, and this video could definitely have been reduced to a 5 second list. Also, the intro was kinda' creepy (not much offense intended).