Not in PHP

In PHP, the not operator is represented by an exclamation point (!). It is used to reverse the truth value of a given expression.

Here are some examples:

1. Checking if a variable is not equal to a specific value:

$num = 10;

if ($num != 5) {

   echo "The value of num is not 5.";

}

2. Using not with logical operators:

$x = 5;

$y = 10;

if (!($x == 5 && $y == 5)) {

   echo "Either x is not equal to 5 or y is not equal to 5.";

}

3. Checking if a string does not contain a specific substring:

$str = "Hello, world!";

if (!strpos($str, "cat")) {

    echo "The string does not contain the word 'cat'";

}

In each of these examples, the not operator is used to reverse the logical result of the expression that follows it.