So, I was wondering, what’s the diffrence between a proof reader and a pre reader?

6854501
Depends on who you ask and in whcih country you are in

i would go with a pre-reader reads the story in a early form, give advice, feedback and tell you what he thinks about it so you can improve it. While a proofreader reads the finished story/chapter to make sure everything is ready. See they as last checkpoint while the pre-reader is there during the process ofd writing every now and then

This group however has:
Proof-reader:
Looks through the story with the main goal to tackle grammar and spelling errors. They don't heavily change things, rather, just take a look at errors. Kind of the "middle-man" between editors and pre-readers, as proof-readers should also provide an opinion on the piece.

Pre-reader:
Focuses on giving a well thought opinion on the piece, and hardly detects errors. The pre-reader should definitely give a lot of feedback on what they thought of the piece, using both good and bad (if applicable) examples.

6854514
Basically similar to my personal definition. I usually say the proofreader focuses on the technical errors and grammar and stuff. Pre-Readers focus on the flow of things and the story aspects, rather than any technical errors. Both are extremely helpful in their own ways.

6854501
My answer is similar to Backslashton.
Proof-reader for me acts more as an editor. Checking for grammar, spelling, sentence structure and giving an overall opinion on what can be improved.
Pre-reader is more to bounce story idea's off of and see if the story itself is good. Pre-reader is like giving the story to a close friend to see what he thinks of it before you publish it.
The two do often over overlap though. It's easy for a pre-reader to notice and point out obvious grammar mistakes, and chances are if someone is really good at correcting grammar they probably have some skill in story critiquing.