HTML is Fine but PHP is not working

[netpants17]

When i make html files and put them into my directory they work fine viewing them from localhost/test.html , but if i were to make a simple print script and turn it into a php file it wont read it and it gives me an object not found 404 error, this is only for php files that I have found so far.
I am trying to learn how to write php and its very difficult because php files are not working.
Any help would be appreciated.

[Wiedmann]

The demopages (http://localhost/xampp/) are not working?