What is the difference between postfix increment and postfix decrement?

The difference in operation order and return value:

• Postfix increment ($i++): First returns the current value of the variable, then increases it by 1.
• Postfix decrement ($i--): First returns the current value of the variable, then decreases it by 1.

Example:

<?php
$a = 5;
$b = $a++; // $b will be 5, $a will become 6

$c = 5;
$d = $c--; // $d will be 5, $c will become 4

Operation	Action	Return value
Postfix increment	Return value first, then increment	Value before increment
Postfix decrement	Return value first, then decrement	Value before decrement