What is the difference between variable and constant?

Question

how to declare in php

Answer 1

A variable can be assigned with any type of information: a text string (string), integers (integer), an array, boolean values(true/false), null, etc; when declaring a variable, you assign it with an initial value.

$variable_name = 'value';

PHP also allows variables change type, i.e. a variable that was formerly a string can be changed to another type of information without any problems.

<?php
$myVar = "hello, this is string";
$myVar = 30;
$myVar = array('this','is', 'an', 'array');
$myVar = true;
?>
The final value of the variable $myVariable will be true, all the rest of the assigned information is lost.

A constant, as the term suggests, is an expression whose value cannot be modified throughout the script and cannot be rewritten. For defining a constant variable, conventionally capitalized names are used. Constants are global in nature.

$ is not used, instead an inbuilt PHP function called define() is used.

Answer 2

thanks dude