Information on the play station portable (PSP)?

Hi, I was wondering if you would tell me all there is to know about psp's. i am new to these systems and I know there are many different types, some newer and some older. Could you tell me about every single one that has been made in precise detail, from the very first one invented to the newest one as of 6-25-11. Also can you review the one you think is best and tell me why. Thanks so much!! This question is worth 10 pts if you give me a good answer!!!