What are Falsy values and Truthy values?

Values that generally returns false is called falsy values in JavaScript. And some falsy values are : “”, 0, undefined, NaN, null, False etc.

Values that generally represents true are truthy values in JavaScript. Some truthy values are : “ ”, ‘0’, [] ,{}, true, 1.

Look closely, here “” an empty string is falsy but a string with just an empty space represents truthy value. Because a space is still something.

What is the main difference between ‘null’ and ‘undefined’?

I will make it easy for you by giving some examples.

Undefined :

a. Not assigning a value in a variable = undefined.

b. Not returning from a…


What is React?

React is a JavaScript Library. It is not a framework. Many people all over the world confuse React with some other frameworks but no it’s not a framework it a Library. Is it complete? Does it have all the solutions we need while building websites? No certainly not. But it’s a lightweight, easy to use component based library which is used all over the world for it’s simple features.

Why React?

Now you may ask why should I use React? I can use any framework I need and they have solutions for some very important problems. So why should I use a…


Primitive Values :

Primitive Values are consisted of string, number, bigint, boolean, undefined, symbol, and null. And these primitive values have something in common. They can not be altered . There’s nothing a programmer can do to affect them.

Sometimes people get confused over primitive values and variables that are assigned with primitive values. Let’s look at it this way, “You can always change the value assigned to a variable cause that’s literally a variable is for. Here you are assigning another primitive value in that variable. You are not changing the previous primitive value.”

Type of :

typeof is a JavaScript keyword that returns the…


JavaScript is a high level, just-in-time complied programming language.

If you go to google and search the top 10 popular programming language right now, the first name you’ll see is JavaScript. So it is clear that we can do some incredible things with this language. But before doing so, we must need to know the basics of this language and have some firm grasp on the various sides of this language. Recently I tried to learn JavaScript and I learned some key features about it. Today I’ll share my learning.

JavaScript Engine :

JavaScript engine is a computer program which executes JavaScript codes. The first JavaScript engine were mere interpreters and created…

Rakib Hasan

Web Developer, Dreamer, Quick Learner.

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