iPhone - difference between photostream and camera roll

Eliza_2

I've googled the above and read loads but still none the wiser. On my photo section I have a photo stream, a camera roll, a folder called work, another called Album 1 and one called videos which mysteriously appeared a few weeks ago. I really need to free up some memory so I can have a few more audiobooks and it seems these photos take up loads of gigs. I want a main folder where everything is stored, I then want to move some pictures out of that into the one called work or another of my choosing. (but not keep them in the main folder) It seems they are all duplicated, and some quadriplicated so no wonder I have no memory left.

Can anyone advise me how to do what I want? Things I've read go on about sharing and icloud and itunes none of which I want. I got rid of itunes on my laptop as that also used too much memory and during a sync got rid of some things I wanted to keep (my fault for not understanding the settings properly)

I read that I could safely de-activate photostream but when I went to do that in settings it said it would delete everything which I didn't want (do I?) so stopped that.

Would be grateful for any help Thanks.

Liz