PHP Variables

PHP Variables is very interesting, its just like a container. PHP Variables data transfer from one place to another place. PHP Variables start with $ sign.

Basic Example:

<?php

$a= 20;
echo $a;

?>

Result: 20

There are two types of Variables :

1. Pre define Variable             2. User define Variables

1) Predefined Variables : These variables are available in PHP program.  There is no need to declare and define these variable in the program. These are following  type of Pre define Variable.

Predefine Variables = Super define variables.

$_GET
$_POST
$_COOKIE
$_SESSION
$_FILES
$_ENV
$_REQUEST
$_SERVER

2) User define Variable : This variable is declare and define by developers

For Example:
$ontime=50;

$ontime is a variable and 50 is a data and this data store in variable $num. So we can use this variable for print the value of 50 at any where as per requirement.

Benefit of PHP Variable : PHP automatically converts the variable to correct data type, depending on value.

Example:

<?php
$a=30;
$b=50;
$c=$a+$b;
echo “First Number is $a”.”<br>”;
echo “Second Number is $b”.”<br>”;
echo “Result is $c”;
?>

Result:
First Number is 30
Second Number is 50
Result is 80