In PHP, how can letters be incremented similar to numbers?

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In PHP, letters can be incremented using their ASCII values. The ASCII value of each letter can be incremented by 1 using the ord and chr functions.

For example, to increment the letter 'a' by 1:

$letter = 'a';
$newLetter = chr(ord($letter) + 1); // $newLetter now equals 'b'

Similarly, to increment any letter by a specific number:

$letter = 'b';
$increment = 3; // Increment alphabet by 3
$newLetter = chr(ord($letter) + $increment); // $newLetter now equals 'e'