Hello everyone. My name is Asfakur Rahman. In this article i want to discuss about something basic bust most important things for all the JS developer. If you have some time, please read my article & follow me. Thank you

Here is a short list that i want to discuss in this article:

  1. Truthy and Falsy values
  2. double equal (==) vs triple equal (===), implicit conversion
  3. Scope, block scope, access outer scope
  4. Closure, encapsulation, private variable
  5. difference between call and apply
  6. Remove duplicate item from an array
  7. Count the number of words in a string
  8. Reverse a string
  9. Create a…

What is React?

React is a Javascript library for building a user interfaces. React create interactive UIs without any type of pain. It helps to design a simple vies for each state in application & it will efficiently update and render only the exact right components when data is changed. React declarative view makes code more easier & more predictable to debuging.

React build up encapsulated components that manage their own state and after that react conpose them to make a complex UIs. Now components logic are writting in Javascript instead of templates, that’s why developer can easily able to…


  1. Error Handling

Error is the most common thing in any type of programming. When an error occurs in programming, that program won’t able to give user output & it will show up what’s the reason that occurs an error in the program.

If there is an error in the code, it immediately terminates the code in the compiler and shows that error in the console.

“try…catch” syntax

There is a syntax called “try…catch”, that allowed a user to catch an error that can do something more than instead of terminating the program.

The “try” statement gives the user to test…


JavaScript is a text-based programming language that used for both on the client-side and server-side, that allows user to make web pages more interactive. Where HTML and CSS are languages that give structure and style to web pages, JavaScript gives web pages interactive elements that engage a user to develop more and more. Common examples of JavaScript that people might use every day in the search bar on Facebook, Youtube, or Twitter.

Here are some of the built-in function that needs to know for a Javascript developer:

String:

  1. String.toLowerCase():

This function is used to convert a string from uppercase to…

Asfakur Rahman

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