Constant Variable Tutorial in PHP

 <?php

define("test",50);
echo test."<br>";

$sum = test + 20;
echo $sum."<br>";//Constant variable works as Normal Variable but we can't Re-assign OR Re-defined
//value again to contant variable

//Contant variables are case sensitive

define("testOne",55);
echo testOne."<br>";

define("_test",100);
echo _test."<br>";
?>


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