Logical operators are used to combine conditional statements.

and

($x and $y) True if both $x and $y are true

$x = 40; 
$y = 50;
if ($x > 30 and $y > 45) {
    echo "True";
}

or

($x or $y) True if either $x or $y is true

$x = 40; 
$y = 50;
if ($x > 30 or $y == 85) {
    echo "True";
}

xor

($x xor $y) True if either $x or $y is true, but not both

$x = 40; 
$y = 50;
if ($x > 30 xor $y == 85) {
    echo "True";
}

&&

($x && $y) True if both $x and $y are true

$x = 40; 
$y = 50;
if ($x > 30 and $y > 45) {
    echo "True";
}

||

($x || $y) True if either $x or $y is true

$x = 40; 
$y = 50;
if ($x > 30 or $y == 85) {
    echo "True";
}

!

(!$x) True if $x is not true

$x = 40;
if ($x !== 50) {
    echo "True";
}