How does the "!" operator work in PHP compared to Java?

In PHP, the "!" operator is used to negate a boolean value. It essentially flips the boolean value from true to false or false to true. In Java, the "!" operator also negates a boolean value in the same way. To use the "!" operator in PHP, simply place it before the boolean expression you want to negate.

$booleanValue = true;
$negatedValue = !$booleanValue; // $negatedValue will be false