PHP Constant

Once constant are defined they can’t be changed and they like a varaible

A constant is a name or an identifier for a simple value.

During the execution the constant value can’t be change , they start with letter, numbers, underscore.A Constant is case senditiv, when you define a constant, it can’t be changed, define() function is used for define a constant.

Example

Define() function. is used to create a constant
<?php
define("ConstantVariable", 50);
echo ConstantVariable;

?>