How can I show 40 images at a time when showing all images in a directory?

[Ethan]

I have a simple php code that shows all images in a directory with 4 images per row. Now what I want to do is only show the first 40 images, then have a next page link at the bottom that will take you to the next 40. How can I do this? 10 points for the best working answer. Thanks!