Before proceeding to programming part first check whether you have installed XAMPP correctly.
You can do this check by typing "http://localhost/" in your browser which shows XAMPP page then
you have done installation perfectly.

First PHP program - hi.php

<?

echo "Hi";

?>

echo is the keyword to print some data. Save the file as hi.php in "c:/xampp/htdocs/" folder.
You can view the output by typing "http://localhost/hi.php" in your browser.

Output

Hi

You can also save your files in an separate folder like "c:/xampp/htdocs/pro/hi.php"
then give url link as "http://localhost/pro/hi.php" Htdocs is the apache web directory
where you can save your web pages. Localhost is like domain name which points to
your webserver.