1. Truthy and Falsy values:
    const name=”shakib”
    console.log(“condition is true”)
    console.log(“condition is false”)
    Output: Condition is true.
    Here, it’s true because the value of the name has a string. if we give their const name=” ”; then the output is condition is false. Because the value of the name is an empty string.
  2. null vs undefined: if a function we don’t return completely or pass a parameter, then it will show output “undefined”.The value null represents the intentional absence of any object value.
  3. double equal(==)vs triple equal(===): when we are using == equal, that means we check both…

React is a library of javascript which is used for building user interfaces.
when a user working with a framework, Many smart design decisions are already made for the user and gives a clear path to focus on writing good application-level logic. We can use React to describe Web UIs.

1)Introduction:In React DOM is “Document Object Model” which is used to change a document structure ,style and it’s also the browser’s programming interface.

2) The React Language: In an array, we store a lot of value. But user can change, add, remove or update data. …

A better programmer best friend is “Error”. It may occur because of our mistakes, and unexpected user input. But we can catch the error by applying.

The “try…cath” syntax:

try{//code} catch(err){//error handling}

It works like this:

  1. First, the code in try {...} is executed.
  2. If there were no errors, then catch (err) is ignored: the execution reaches the end of try and goes on, skipping catch.
  3. If an error occurs, then the try execution is stopped, and control flows to the beginning of catch (err). …
  1. String.concat;
    String.concat is used to add two string and get one .

const string1= ‘Hello’;
const string2=’world’;

console.log(string1.concat(‘ ‘,string2));
//Output : “Hello world”

console.log(string2.concat(‘ ‘, string1));
//Output : “world hello”

2) String.charAt()
String.charAt() used to find out specific position of a character from the string.

const sentence1 = “Hello world”;
const index1= 4;
console.log(`The character at index ${index1} is ${sentence1.charAt(index1)}`)
//Output : “The character at index 4 is o”

String.includes() is used to find out one string within another string and returning true and false.

Example: const sentence = ‘Hello World.’;

const word = ‘Hello’;

console.log(`The word…

Sudipto Acharjee

Web Developer

Get the Medium app

A button that says 'Download on the App Store', and if clicked it will lead you to the iOS App store
A button that says 'Get it on, Google Play', and if clicked it will lead you to the Google Play store