How do you declare a PHP variable?

 In PHP, you declare a variable using the dollar sign ($) followed by the variable name.

Syntax:

php

$variable_name = value;

Examples:

php

<?php
$name = "John";
$age = 25;
$price = 99.50;

echo $name;
echo $age;
?>

Rules for declaring PHP variables

1. A variable must start with a $ sign.

2. The variable name must start with a letter or underscore (_).

3. A variable name cannot start with a number.

4. Variable names are case-sensitive ($name and $Name are different).

5. You do not need to specify the data type.

Remember: PHP variables are declared automatically when you assign a value to them. You don't need a keyword like int, string, or var.