How can the PHP code be optimized to avoid redundancy and improve efficiency?

To optimize PHP code and avoid redundancy, you can utilize functions to encapsulate repetitive logic and improve efficiency. By creating reusable functions, you can reduce the amount of code duplication and make your code easier to maintain and debug.

// Example of optimizing PHP code by using functions
function calculateArea($length, $width) {
    return $length * $width;
}

$length = 10;
$width = 5;

$area = calculateArea($length, $width);
echo "The area is: " . $area;