If the current day is Friday the code will output "Have a nice weekend!" PHP datetime format: https://www.php.net/manual/en/datetime.format.php

$d = date("D");
if ($d == "Fri"){
    echo "Have a nice weekend!";
}

If the current hour is less than 20, the code will output "Have a good day!"

$t = date("H");
if ($t < "20") {
  echo "Have a good day!";
}

If

$age

is more than

18

, prints

Adult

$age = 20;
if ($age > 18) {
	echo 'Adult';	
}