PHP DATA TYPES

Variables can store data of different types, and different data types can do different things.

PHP supports the following data types:
String
Integer
Float (floating point numbers - also called double)
Boolean
Array
Object
NULL
Resource 

PHP String

A string is a sequence of characters, like "Hello world!".
A string can be any text inside quotes. You can use single or double quotes:

<?php
$x = "Hello world!";
$y = 'Hello world!';

echo $x;
echo "<br>";
echo $y;
?>

PHP Integer

An integer data type is a non-decimal number between -2,147,483,648 and 2,147,483,647.
Rules for integers:

An integer must have at least one digit
An integer must not have a decimal point
An integer can be either positive or negative
Integers can be specified in three formats: decimal (10-based), hexadecimal (16-based - prefixed with 0x) or octal (8-based - prefixed with 0)

In the following example $x is an integer. The PHP var_dump() function returns the data type and value:

<?php
$x = 5985;
var_dump($x);
?>

PHP Float

A float (floating point number) is a number with a decimal point or a number in exponential form.
In the following example $x is a float. The PHP var_dump() function returns the data type and value:
<?php
$x = 10.365;
var_dump($x);
?>

PHP Boolean

A Boolean represents two possible states: TRUE or FALSE.
$x = true;
$y = false; 

PHP Array

An array stores multiple values in one single variable.
In the following example $cars is an array. The PHP var_dump() function returns the data type and value:

<?php
$cars = array("Volvo","BMW","Toyota");
var_dump($cars);
?>