Data types in JavaScript

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There are many types of data in JavaScript, but mainly two types of data and they are the Primitive data and Reference data.

There are many things to say about these two types of data, but without confusing you guys, Primitive Data Types are data that are stored directly on the location the variable accesses. This means when you access primitive data you access it by its mains values. Reference data types are stored in a pointer location on the memory.

Examples of Primitive data (6)

I used a few yesterdays but I did not talk about it, but you can get something if you read both tutorials.

• String
• Boolean
• Number
• Null
• Undefined
• Symbols (Introduced in ES6)

Reference Data

• Object Literals
• Arrays
• Functions
• Dates
• Others that can be stored

So, let's talk about the PRIMITIVE DATA TYPES

// String

const name = 'vidder';

console.log(typeof name); 
This will log on the console that it is a string. 

// Number- if  you put quotes around the number it will turn to a string

const score =  48;

console.log(typeof score);  

// Booleans are true or false - if you put a quote around Boolean it will turn to a string

const sportMan =  true;
console.log(typeof sportMan);  

// Null

const ball = null;

console.log(typeof ball);  

// You will get Object. This is a kind of little mistake in the JavaScript world. This does not mean Null is an object, it is a primitive type but mistakenly picked as object. 

// Undefined 

let phone;

console.log(typeof phone);  

// Symbol

const sym = Symbol();

console.log(typeof sym);  

These are all the Primitive types in JavaScript. I hope you understand them, but you could ask questions on the comment section if you have issues with anyone.

Let's get to REFERENCE TYPES.

All reference types will come back as Object.

// Array

const sports = ['Football', 'Basketball', 'Cricket', 'Rugby']; 

console.log(typeof sports);

// Object Literals

const address = {

country: 'USA',

state: 'Las Vegas'
}

console.log(typeof address);

// Date

const today = new Date();

console.log(today);

console.log(typeof today);

// In date aspect, the first log will show the current date and the type will show object. 

These are the basics you need to know about Data types in JavaScript. You can pop on comments if you have questions. I will build a simple system tomorrow and I will try to continue a little with this JavaScript progressive tutorial.

Thank you!