A data type is a classification identifying types of data such as string, boolean or numbers. It determines the possible values for that particular type.

JavaScript Data Types

Here's a useful video related to the topic:

JavaScript is a loosely typed or a dynamic language. That means you don't have to declare the type of a variable ahead of time.

The latest ECMAScript standard defines seven data types:

► Six data types that are primitive:

• Number
• Boolean
• String
• Symbol (new in ECMAScript 6)
• Null
• Undefined

► and an Object

To learn about the difference between primitive data types and objects, click here.

Numbers

Numbers can be written with or without decimals. They can also be written in scientific (exponential) notation.

_EXAMPLE

var num1 = 42;      //Written without decimals. 
var num2 = 42.00;   //Written with decimals.
var num3 = 2e5;     //200000
var num4 = 2e-5;    //0.00002

Booleans

Boolean can only have two values: true or false.

_EXAMPLE

var a = true;   
var b = false;

Strings

A string is written with quotes. It can be written using single or double quotes.

_EXAMPLE

var website = "hackerrank";   // Using double quotes
var website = 'hackerrank';   // Using single quotes

Symbol

A symbol is a unique and immutable data type and may be used as an identifier for object properties. To create a new primitive symbol, you simply write Symbol() with an optional string as its description.

_EXAMPLE

var sym = Symbol();
var sym1 = Symbol("foo");

Null

In JavaScript, null is "nothing". It is supposed to be something that doesn't exist.

_EXAMPLE

var data = null;

Undefined

In JavaScript, a variable without a value has the value, undefined. Also, any variable can be emptied by setting the value to undefined.

_EXAMPLE

var data;       //It has type undefined
var data1 = undefined;

Object

An object is a collection of properties. The properties are identified by using key values. Property keys are used to access the properties and their values.

Object properties are written as key:value pairs separated by commas.

_EXAMPLE

var car = {color:"black", model:"X", mileage:30};

Task

Your task is to:

• Create a variable my_num and assign it any number.
• Create a variable my_bool and assign it any boolean.
• Create a variable my_str and assign it any string.