How can PHP functions be used to modify variable content effectively?

To modify variable content effectively in PHP, you can create custom functions that take the variable as an argument, manipulate its content, and return the modified value. This allows you to encapsulate the logic for modifying the variable in a reusable way.

// Function to add a prefix to a string variable
function addPrefix($variable, $prefix) {
    return $prefix . $variable;
}

// Example usage
$originalString = "Hello";
$modifiedString = addPrefix($originalString, "Prefix_");
echo $modifiedString; // Output: Prefix_Hello