Non destructive, batching in LR questions?

Ok, I looked high and low and I can't seem to understand what NON destructive in LR for photos mean. I mean I think I understand it but if I had a picture on my desktop and I import it into LR and start changing the exposure, etc., non destructive mean that my original copy on my desktop doesn't change?

I don't get it?

I use/d ACDSEE (slowly transitioning to LR) and basically with ACDSee if I had a picture on my desktop, any changes I do in ACDSEE will change the original...of course it will also ask me whether I want to "save as" the changes. So in that light, it's technically manipulating the original.

Also, another neat thing with ACDSee is the ability to batch rename and batch conversion, batch etc. Does LR have the ability to do the same?

I'm presuming that if I had a set of pictures in a folder, all LR does is import the "information" and catalogues it but doesn't really organize them (the actual photos), like in ACDsee if I move it around in ACDsee.

Non destructive edits are edits that can be undone. In LR edits are not made to the original file, they are stored in a database. So each time you make a change to the file you are seeing the file as a rendered copy of the original with the edits applied.

This thread has info on batch processing in Lightroom:

https://photography-on-the.net/forum/showthre​ad.php?t=347015

Thanks IN2Photos...didn't see that thread.