Javascript Introduction
Comments in Javascript
Javascript Variables
Difference between var, let and const in Javascript
Datatypes
Assignment Operators
Logical Operators
Comparison Operators
Actions alert, prompt & confirm

Javascript Flow Control
Conditional Statements in Javascript
Nullish coalescing operator in Javascript
Break and Continue in Javascript
Loops in javascript
for loop in Javascript
while loop

Javascript Functions
Javascript Functions
JavaScript Arrow Function

Javascript Objects
Javascript Objects

Javascript Array
Javascript Arrays

Javascript Error Handling
Error Handling in Javascript

Javascript ES6
Set
Javascript Spread Operator
Rest Parameter in Javascript

Javascript Asynchronous
Javascript Callback Function
Promises in Javascript
Promise Chaining
Async-Await in Javascript

Javascript DOM
DOM Document
DOM Elements
DOM Attributes
DOM Manipulation
DOM Node Lists
Javascript Events
DOM Traversing Elements
DOM EventListener

Javascript Class
Classes in javascript
Class Inheritance

Javascript Design Principles
SOLID - The Single responsibility principle in javascript
SOLID - Open-Closed principle in Javascript

Other Topics
Javascript Hoisting
Filter, Map and Reduce functions in Javascript
Closure in Javascript
Optional chaining operator in Javascript
Consoling in table format in javascript
Fetch API in Javascript
HTML web Storage API
Checking the online or offline status of the browser

Javascript Hoisting

Hoisting is a concept that is available in javascript by default. It is a behavior of moving all the declarations to the top.

Example

            greetMessage = 'Welcome to ReadersBuddy';

let greet = document.getElementById('message');
greet.innerHTML = greetMessage;

var greetMessage;

The above code will be reorganised as

            var greetMessage
greetMessage = 'Welcome to ReadersBuddy';

let greet = document.getElementById('message');
greet.innerHTML = greetMessage;

This will generate display the result as

Welcome to ReadersBuddy

Note:

If we declare the variable greetMessage as let and const then it will not be hoisted.
Javascript only hoists the declaration, not the initializations.

Let's modify the above code as below.

            let greet = document.getElementById('message');
greet.innerHTML += greetMessage;

var greetMessage = 'ReadersBuddy';

This will display the output as

undefined

Javascript Hoisting

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