The most commonly used HTTP verbs POST, GET, PUT, DELETE are similar to CRUD (Create, Read, Update, Delete) operations in database.

verb: POST

1) POST: POST method means Create new resources. On successful creation, return HTTP status code 201, returning a locaion header with a link to the newly-created resource.

verb: GET

2) GET: We can read-only by GET method. Ex. In browser address bar we type a link. It instruct the server to transmit the data indentified by the url to the client. client only read this data. In this sense, a GET request is read-only. HTTP response code 200 (OK). …


A web server is a software and hardware that uses HTTP(Hypertext Transfer Protocol) and other protocols to respond to the client requests made over the WWW. The main job of a web server is to display website content through storing, processing and delivering webpages to users. Beside HTTP, web servers support SMTP(Simple Mail ..) and FTP (File ..) used for mail, file transfer and storage.


js Math.abs() method returns the absolute value of a number. If the given number has (-), it avoids the (-) sign and returns the absolute value.


1.Truthy and Falsy Values:

  1. Truthy: true, “String”, {}, [], and all values are truthy
  2. Falsy: false, 0, “”, null, undefined, NaN, -0, 0n

2. null vs undefined:

  1. null: null used for intentionally missing values. It is also one of the primitive values. null is a falsy value for boolean operations.
  2. undefined: undefined unintentionally missing values. It is also one of JavaScript’s primitive values. undefined is also a falsy value. When just declare a variable, not initialization, the get undefined

3. double equal (==) vs triple (===):

double equal and triple equal compare two things. But double equal (==) compare two…


1. It is a library not a framework.

A framework is a combination of some modules and common things. Some decisions are already made for you. But React is just a library and you need to make all decisions by yourself. It helping you to build user interfaces using components. React is easy to build web apps and easy to use 3rd party libraries.

2. JSX

jsx means javaScript XML. Write HTML code in js and also write js code into HTML that is JSX. For example:


1.Hoisting: Hoisting suggests that variable and function declaration are moved to the top of your code before execution.

The above code snippet is we call the function before we write the function and the code still works.

only declarations of the variable are hoisted, not initialization.


The Number.parseFloat() method returns floating-point of an argument. If the argument isn’t parsed, it returns NaN.

The Number.parseInt() and Number.parseFloat() are the almost similar. ButNumber.parseInt() returns only Integer.


NaN means not a number.

The Number.isNaN() method check whether the provided value is NaN and its type is number. The given value is to be exactly NaN.

isNaN() method returns true if given arguments is not a number. And return false if the given value is a number.


charAt(), concat(), includes(), endsWith(), indexOf(), lastIndexOf(), replace(), slice(), split(), startsWith(), substr(), toLowercase(), toUppercase(), toString(), trim(), trimStart(), trimEnd()

1.charAt(): We can get any character of a string for an index number. If you don’t put the index num inside the charAt(), it will return the 1st character because the default value is 0. And the given index is out of the range of the string, then it will return an empty string.

2. concat(): The concat() function is the concatenation of the provided arguments and returns a new string.

Mainul Islam Faruqi

I am a full-stack web developer. Programming makes our life better. Writing code is my hobby. I am very passionate to write code.

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