define variable in javascripo code example

Example 1: how to declare variables javascript

//variables are a way to easily store data in javascript
//variables are declared by the var keyword, example...
var x = 10;
//or
var dog_name = "daisy";
//which can also be written as 
var dog_name = 'daisy';
//same thing with single quotes and double quotes

Example 2: javascript variables

// Also let, const
var e_number = 0;
var e_string = '';
var e_true = true;
var e_false = false;
var e_undefined = undefined;