PHP files?

I was going through some old files when I stumbled across some PHP files. I know that it holds images, I remember puting them together on a windows program, but for the life of me, I can't figure out how to get the files to open. I've tried downloading stuff off of www.php.net, but I don't know how to work that, or even if its the right stuff to be looking at.

Anyone have any ideas?

Open them in Notepad. If they contain gibberish, they have the wrong extension. Otherwise, figure out what they do.