Exploring JavaScript Data Types and Variable Declarations📦📊🖥
Table of contents
“You should imagine variables as tentacles, rather than boxes. They do not contain values; they grasp them—two variables can refer to the same value.”-Marijn Haverbeke
What is a Variable?
A variable can be defined as a container for storing data item values. Javascript variables can be declared using: var, let or const.
NOTE
JS Datatypes
Below are some of the datatypes in Javascript :
- Strings: a series of characters enclosed in single or double quotes.
-Numbers: numbers can be either be integers(whole numbers) or floating points (decimal numbers).
-Booleans: this datatype can only have two values, true or false.
-Arrays: this is an object that contains multiple values at once. Arrays are enclosed in square brackets [ ].
-Objects: This is a datatype that contains properties with values, separated by commas, enclosed in curly brackets { }.
The typeof operator
The typeof operator is used to find the data type of a Javascript variable.
typeof "Gracetoffy"// returns string
typeof 278 // returns number
var book = {
title:"Harry Potter",
author: "J.K Rowling",
rating:4.9 ,
no_of_series: 7
};
typeof book // returns object
var a = 24;
var c = 24;
var equal = a==c
typeof equal // returns boolean
var books =[ "Harry Potter", "Beautiful Creature",
"A Midsummer’s dream", "39 clues"]
typeof books //returns object
Thanks for reading :) !!