10 Important Topics of ES6 — JavaScript

1. Variable declarations and hoisting in ES6
Storing a value in a word or something is called variable in terms of Programming language. There was a time when in some programming language we didn’t have to declare variable(Basic). But as time goes variable declaration becomes more user friendly. In ES6 of JavaScript there are two types of variables 1. let and 2. const. Var used for a variable which might be a changeable value and const use for the value which is always constant.

Hosting lifts the variable to the highest point of the block. It’s an ignored conduct of JavaScript. You Must Understand the hosting to keep away from the bugs. Hosting in Javascript is when Javascript moves variable assertions (NOT definitions) up to the highest point of its worldwide or nearby extension or local scope. Variables like var, const, and let are interpreted as if it is at the top of its scope.

2. Block-Level Declarations in ES6:

Block-level announcements or declarations are the ones that proclaim variables that are far outside of a given scope of block. And block-scope has another recognition, which is called “Lexical Scopes”. They are created either inside of a function or inside of a block.

Let and const are the most recent ways for variable declaration gives by es6. These two watchwords help a developer to evade his normal errors by utilizing block-level perusing.

3. Block Binding in Loops in ES6:
It’s a territory where a web developer needs the block level checking of factors inside for loops and the easy-going factors utilized inside just for the loops. The variable will be decimated once the loop is finished and not, at this point usable.

4. Global Block Bindings in ES6:
In the event that you think about the variable assertion, you should realize that variable can be proclaimed inside or outside of the function before it’s utilized. Now and then you proclaim your factors outside of the capacity. It’s called Global Scooping or Global Block Binding official.

Function Related Topics

5. Functions with Default Parameter Values:

The default parameter is an approach to set default value for functional parameters a worth is no passed in.

It’s a parameter that permits us to instate functions with default values. It tends to be anything from a number to a function. It set an alternate worth and it helps to set the value.

6. Working with Unnamed Parameters:

Unnamed parameters function means an anonymous function. An anonymous function is a function that is declared without any named identifier to refer to it. As such, an anonymous function is usually not accessible after its initial creation.


const hello = () => {

const name = “Md. Jidanul Hakim Jitu”;

return name;



7. The Spread Operator:
Simply spread operator means a syntax of three dots.

Spread sentence structure (…) permits an iterable, for example, a cluster articulation or string to be extended in places where at least zero contentions or components are normal, or an article articulation to be extended in places where at least zero key-esteem sets are normal.

The spread syntax expands array elements and inputs each element into the array individually. It can be used to convert the string into an array. It is also used to expand the array in places where zero or more elements are expected.

8. Block-Level Functions:

The block-level assertion is regularly called a compound assertion in different dialects. It permits you to utilize numerous explanations where JavaScript anticipates just a single statement. Joining statements into blocks is a typical practice in JavaScript.
It behaves the same way as let and const. In ES6, block-level function declarations have block scoping in strict mode. It’s a function that declares only reference within a single block.

9. Arrow Functions:
ES6 introduced us to the arrow function. An arrow function is a function that makes the function shorter than the traditional function in JavaScript. It’s more optimized. This method is the easiest way to declare a function. It can also be used with or without declaring parameters or something called anonymous function. The new arrow functions bring a helpful function syntax to es6 but there have too many confusing syntaxes.

const number = (first * second) => {

production = first * second;

return production;


Exceptional Topics

10. Try_Catch:
try/catch is a statement that handles the entirety of the mistakes in a solitary square of code that occurred by software engineers or some specialized issues in any event, running code. In the explanation of try method/statement, there has an trying or attempted block that contains one just as more articulations that consistently be utilized in any event, for a solitary assertion and it gives three structures for the try statements.

For the easy explanation, it can be said that, try/catch is more likely if/else statements. We can order to computer , try this thing first and if you can’t do that catch the error and make us show the error.

try {

console.log(“You are awesome”);


catch(err) {

I am a goal-oriented problem solver with energy for web development, who might want to join a group of similar engineers.

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