A variable is named storage for data. We use variables to store data that can be recalled when needed.

const points = 100;
//using const will not allow the variable to be changed
//only use const if you know you will not need to change the variable

let age = 25;
//using let allows us to change the variable

age = 30;
//no need to add the let keyword when changing the same variable

var score = 25;
//this is the old type of variable but is still valid
//many developers still use var

//spaces are not allowed in variables
let myCount = 100; //this is ok
let my Count = 100; //this isn't ok

//variables can't start with a number
5mySpace = "100"; //this isn't allowed

//variables can't use keywords that are reserved for javascript
let const = 100; //this isn't allowed

//use camal-case to make variables clearer
let mySpace = 'big room'; //this works and looks neater
let myspace = 'big room'; //this also works
let MYSPACE = 'big room'; //and so does this

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