Loading a Random Image "Question"

Hello I am new here and really have been enjoying all the wonderful tutorials that are offered here. there was one that i came across for being able to display random splash images each time you visit a site and it showed how you use a php file with arrays to set this up.

I just wanted to find out once you place the location to all the images that you want you use and you save your php file and load it to your server is that all that you have to do?

Do you need any other steps e.g. placing any code in your html file, etc or is just creating the php file and loading it where your site files are work fine.

Thanks very much and hope this is the right place to post this. :devious: