1. let vs var vs const
    All three keywords are used to declare variables in JavaScript, but there are slight differences that sometimes gets unnoticed by developers. All these three keywords play different roles while declaring variables, but a lot of times people end up having misconceptions about the way we declare variables in JavaScript.

  2. Dot & Square Bracket Notation
    Both of the notation is used to access properties in objects but in the case of Square Bracket Notation, we can access properties dynamically.

  3. this Keyword
    One of the most confusing concepts in JavaScript, this keyword can be quite confusing if you don’t know how it works under different conditions. As you might be familiar this keyword passes a reference to the current object, but that’s not how it works all the time in JavaScript.

  4. Binding this
    In JavaScript, we can use the bind method to fix the problem that we discussed in the above section, as we aren’t able to access the user object in both cases. Using the bind method you can simply bind an object to a function.


4 Concepts You Shouldn't Miss While Learning  JavaScript
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