Data type specifies the type of value a variable requires to do various operations without causing an error. By default, PHP provides the following built-in data types:

• String
• Integer
• Float
• Boolean
• Array
• NULL

1. String

A string is a sequence of characters that holds letters and numbers. It can be anything written inside single or double quotes.

For Example:

<?php
$x = "Hello world!";
echo $x;
?>

2. Integer

An integer is a non-decimal number typically ranging between -2,147,483,648 and 2,147,483,647.

<?php
$x = 55;
var_dump($x);
?>

3. Float

A float is a number with a decimal point. It can be an exponential number or a fraction.

<?php
$x = 52.55;
var_dump($x);
?>

4. Boolean

A Boolean represents two values: True or False.

<?php
$x = true;
$y = false;
?>

5. Array

Array is a collection of similar data elements stored in a single variable.

<?php
$x = array("Rohan", "Lovish", "Harry");
var_dump($x);
?>

6. NULL

Null is a special data type with only one value which is NULL. In PHP, if a variable is created without passing a value, it will automatically assign itself a value of NULL.

<?php
$x = null;
?>