PHP constant, PHP define constant, - PHP Constant - PHP Tutorial - 10

What is PHP Define Constant ?
In php constant is a variable, one it defined then, it cannot be changed during the script execution. There three parameters in this, name, value and case-insensitive. For creating a constant, use the define() Function. constant variable must be started with any letter or underscore.

Syntax of constant:-
define(name, value, case-insensitive)

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