++ increment operator
-- decrement operator
Example Name Effect
---------------------------------------------------------------------
++$a Pre-increment Increments $a by one, then returns $a.
$a++ Post-increment Returns $a, then increments $a by one.
--$a Pre-decrement Decrements $a by one, then returns $a.
$a-- Post-decrement Returns $a, then decrements $a by one.These can go before or after the variable. Putting this operator before the variable is slightly faster.
If put before the variable, the increment / decrement operation is done to the variable first then the result is returned. If put after the variable, the variable is first returned, then the increment / decrement operation is done.
For example:
$apples =10;for($i =0; $i <10;++$i){
echo 'I have '. $apples--." apples. I just ate one.\n";}