PHP

define in php

//define() is used to create constants
define(name,value);
//here name has to be a string
//here value can be string, integer, float, boolean or NULL, 
//and can be an array to if you are using PHP 7.0+

//define() before php 7.3
define(name,value,case_insensitive);
//case_insensitive is optional and can be TRUE or FALSE by default its false

define php

define("name", {value});

define function in php

<?php

function addTwoNumbers($number1, $number2){
    echo "Result: ",$number1+$number2;
}

addTwoNumbers(100, 125);
?>