i don't get the point of it...but i would really love to know how to mask images and the purpose of it i just want to know the basics of how and what masking is ...it would be really nice to give some short tutorials.......

http://www.createblog.com/forums/lofiversion/index.php/t78679.html

That tutorial is for PSP 8, though I don't doubt it will work in PSP 9 as well.