What are best practices for passing values to functions in PHP?

When passing values to functions in PHP, it is best practice to use parameters to send data into the function. This allows for flexibility and reusability of the function. Additionally, it is important to properly sanitize and validate the input data to prevent security vulnerabilities and unexpected behavior.

// Example of passing values to a function in PHP
function calculateSum($num1, $num2) {
    $sum = $num1 + $num2;
    return $sum;
}

$number1 = 5;
$number2 = 10;
$result = calculateSum($number1, $number2);

echo "The sum of $number1 and $number2 is: $result";