I hope that you are a javaScript learner & you are already learn more with js. Today I will introduce you to some of the core concepts of JavaScript that you must know as a JavaScript programmer.

Truthy….Falsy

Truthy….falsy??? Yes, the first topic of my article is truthy….falsy.

· Simply remember that any numbers type data is truthy without 0. Also remember not to set any number type data inside the double quotation.

· Without empty string any string type data is truthy.

I will try to understand this with some example :


I hope you already know about React JS and can create at least one puchka application using by React JS. But do you know? How does react js work? Right now it’s make you a confusion? 🤦🏼‍♂️ Am I right or Am I right?

Don’t worry about it? Let’s start with me………………….

How does react js work???? 🤷🏼‍♂️

How would you feel if you could write HTML code in JavaScript? Yes, and we will use React to do that.

Creating the representative of a DOM node can be done through creating the Element function in React. Here is an example of it:


JavaScript Concepts

Error Handling………

Overview :

No matter how great a programmer you are, some mistakes can cause the program to stop. Or the program may stop due to incorrect input from the user, or the server may not respond properly, even then the program may stop. To protect the program from this stop, you need to have an idea about error handling.

Suppose, I did a coding of 100 lines. I have an error in line 3. In this case, if I use error handling, the program will not stop for of my mistake in line 3. The program will continue by skipping line 3…


Let’s play with JavaScript array
Let’s play with JavaScript array

1.0 — Do you know what is array? 🙋🏼

Array is one kind of variable where we can store multiple data in a single variable. Arrays are used when we want to access elements in an orderly fashion using a single variable. We can store strings, boolean and numbers in a single array.

What we can store in JavaScript array????

JavaScript array is dynamic array. Do you know, what does dynamic array mean? 🤷

Dynamic array means:

  • Don’t need to specific array length.
  • Dynamically increase or decrease array size.
  • Don’t need to collected garbage.
  • Can store any kind of data.


I start learning JavaScript for last 3 months. As a beginner, I face a lot of questions & problems. One of them is Why should I use let or const instead of var. I watch many tutorials about this. When I watch all those tutorial I decided to use Var as a beginner. Because the first method I learned about the variable declaration is var. And it is easy to use. But later when I start working on project I face many bugs and issues. Now I explain which one we should use.

Naming Variables :

At first I discuss of variable naming…

M.A Fayez

Frontend Developer

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