What improvements can be made to the provided PHP code to enhance performance and readability?

The provided PHP code can be improved for performance and readability by utilizing PHP's built-in functions and optimizing the code structure. One way to enhance performance is to reduce unnecessary loops and function calls. To improve readability, we can use more descriptive variable names and add comments to explain the code logic.

// Improved PHP code for performance and readability

// Original code
$numbers = [1, 2, 3, 4, 5];
$sum = 0;
foreach ($numbers as $number) {
    $sum += $number;
}
echo $sum;

// Improved code
$numbers = [1, 2, 3, 4, 5];
$sum = array_sum($numbers);
echo $sum;