How can one round numbers in PHP to a specific number of decimal places?

To round numbers in PHP to a specific number of decimal places, you can use the built-in function `round()`. This function takes two arguments: the number you want to round and the number of decimal places you want to round to. Simply pass the number and the desired decimal places as arguments to `round()` to achieve the desired result.

$number = 123.456789;
$rounded_number = round($number, 2); // rounds to 2 decimal places
echo $rounded_number; // Output: 123.46