ES6 refers to version 6 of the ECMA script programming language. … is a major extension of the JavaScript language, and adds many more features aimed at simplifying large-scale software development. ECMAScript, or ES6, was published in June 2015. It was later renamed ECMAScript 2015.

Variable:

1. Here are 3 ways to declare a JavaScript variable:

• Var
• Let
• Const

A variable is a container for storing data

Below is how to declare a variable:

Example:

• var: var keyword is a global scope variable declared.

• var: Let: The keyword let declare a block scope variable. It is confined within the scope. The variable cannot be re-declared with let, but its value can be changed.

Example:1

Example:2

Example:3

• Const: The const keyword declares a JavaScript variable with a constant value. Constants are like let variables, values ​​cannot be changed. With const Declared variable blocks have scope.

Example: 1

Example: 2

Default parameters:

• The default function allows the parameters named parameters to start with the default value if there is no value or unspecified pass.

Example:

Template string:

• Template use back-tick () instead of quotes ("") to define a string.

Example: 1

In Template Literal, both single and double quotes can be used inside a string.

Example: 2

• The template allows literally multi line strings

Example: 3

• Template literals provide an easy way to expand variable expressions into strings. This method is called string interpolation.

Example: 4

Spread Operator:

• The JavaScript spread operator (…) can copy all data from an existing array or object to another array or object.

Example:

Arrow Functions:

• The arrow function allows us to write the short function syntax:

We used to write functions like this:

Example:1

Arrow Function:

Example:2

• If the function does not need to be a parameter and returns a single value, then the direct function can be written without a cursor. Then the function becomes smaller.



Example:3